The Place Of Coca Leaf In The Living World

(from) Chapter 11

The History of Coca (1901)

By Dr. William Golden Mortimer , MD

(in) The Coca Leaf Papers (2014)

By Bill Drake

 In previous posts I have presented various excerpts from Dr. Mortimer’s excellent book, which not only contains a wealth of highly relevant information but illustrates the often-acknowledged but poorly understood fact that human beings keep re-discovering the insights of those gone before them, treating such “discoveries” as new knowledge.

Dr. Mortimer’s book also vividly demonstrates how easily knowledge is lost, or deliberately set aside, in pursuit of the agenda of the times.

It is impossible to estimate how many millions of people are suffering and dying right this moment because the agenda of our times has demonized Coca Leaf as part of a worldwide set of political and economic agendas conceived in ignorance and maintained with malice regarding the place of natural medicines in treating and healing diseases that arise naturally and diseases that are caused by external agents, almost always in pursuit of profit.

In both cases, access to pure, natural Coca Leaf for self-treatment would undermine the political and economic agendas of powerful groups, and so we suffer and die, by the millions each year, in servitude to these cruel and heartless sub-humans.

In my continuing protest against this overwhelming flood of power and money that is drowning the planet, I offer this excerpt from a chapter in “The History of Coca” in which Dr. Mortimer explains the place of Coca in the natural world, and the processes by which its magical properties occur. Perhaps you, the reader, will be one more voice raised against the denial of this potent natural medicine to all those suffering, dying people whose lives could be mended and saved simply by having access to this miraculous leaf. 

The Place Of The Coca Leaf In The Living World

In the Coca leaf, as indeed in all plants, the cell wall is made up of cellulose, a carbohydrate substance allied to starch, with the formula xC₆H₁₀O₅. The material for the building of this substance, it is presumed, is secreted by the cell contents or by a conversion of protoplasm under the influence of nitrogen. This product is deposited particle by particle inside of the wall already formed. Accompanying this growth there may occur certain changes in the physical properties of the cell as the wall takes in new substances, such as silica and various salts, or as there is an elaboration and deposit of gum, pectose and lignin. Each living cell contains a viscid fluid, of extremely complex chemical composition – the protoplasm – a layer of which is in contact with the cell wall and connected by bridles with a central mass in which the nucleus containing the nucleolus is embedded. The protoplasm does not fill the whole cavity of the cell, but there is a large space filled with the watery sap.

The sap carries in solution certain sugars, together with glycogen and two varieties of glucose, and such organic acids  and coloring matters as may already have been elaborated.  Where metabolism is active, certain crystallizable nitrogenous bodies, as asparagin, leucin and tyrosin, with salts of potassium and sodium, are found, while in the vacuole there may be starch grains and some crystals of calcium oxalate. The  protoplasm is chemically made up of proteids, of which two groups may be distinguished in plants. The first embracing  the plastin, such as forms the frame work of the cell, and the second the peptones of the seeds, and the globulins found in the buds and in young shoots. These proteids all consist of carbon, hydrogen, nitrogen, oxygen, and sulphur, while plastin also contains phosphorus. In active growing cells the proteids are present in a quantity, which gradually diminishes as the cell becomes older, leaving the plastin as the organized proteid wall of the cell, while the globulins and peptones remain unorganized. The whole constructive metabolism of the plant is toward the manufacture of this protoplasm, the chemical decomposition and conversion of which liberates the energy which continues cell life.

In certain cells of the plant associated with the protoplasm, and presumably of a similar chemical composition, are little corpuscles, which contain the chlorophyl constituting the green coloring matter of plants, a substance which from its chemical construction and physiological function may have some important influence on the alkaloid formation in the Coca leaf. In these bodies the chlorophyl is held in an oily medium, which exudes in viscid drops when the granules are treated with dilute acids or steam. Although no iron has been found in these bodies by analysis, it is known that chlorophyl cannot be developed without the presence of iron in the soil. Gautier, from an alcoholic extract, calculated the formula C₁₉H₂₂N₂O₃, and called attention to the similarity between this and that of bilirubin, C₁₆H₁₈N₂0₃ – the primary pigment forming the golden red color of the human bile, which possibly may be allied to the red corpuscles of the blood. Chlorophyl, while commonly only formed under appropriate conditions of light and heat, may in some cases be produced in complete darkness, in a suitable temperature. Thus if a seed be made to germinate in the dark, the seedling will be not green, but pale yellow, and the plant is anӕmic, or is termed etiolated, though corpuscles are present, which, under appropriate conditions, will give rise to chlorophyll.

It has been found that etiolated plants become green more readily in diffused light than in bright sunshine. The process of chlorophyll formation neither commences directly when an etiolated plant is exposed to light, nor ceases entirely when a green plant is placed in darkness, but the action continues through what has been termed photo-chemical induction. From experiments to determine the relative efficacy of different rays of the spectrum it has been found that in light of low intensity seedlings turn green more rapidly under yellow rays, next under green, then under red, and less rapidly under blue. In intense light the green formation is quicker under blue than under yellow, while under the latter condition decomposition is more rapid.

The function of chlorophyl is to break up carbonic acid, releasing oxygen, and converting the carbon into storage food for the tissues, the first visible stage of which constructive metabolism is the formation of starch. The activity of this property may be regarded as extremely powerful when it is considered that in order to reduce carbonic acid artificially it requires the extraordinary temperature of 1300° C. (2372° F.). In the leaf this action takes place under the influence of appropriate light and heat from the sun in the ordinary  temperature of 10°-30° C. (50°-86° F.). Plants which do not contain chlorophyl – as fungi – obtain their supply of carbon through more complex compounds in union with hydrogen.

Perhaps we are too apt to regard plants as chiefly cellulose – carbohydrates, and water, without considering the importance of their nitrogenous elements, for though these latter substances may be present in relatively small proportion, they are as essential in the formation of plant tissue as in animal structures. The carbohydrates of plants include starch, sugars, gums, and inulin. The starch or an allied substance, as has been shown, being elaborated by the chlorophyl granules, or in those parts of the plant where these bodies do not exist, by special corpuscles in the protoplasm, termed amyloplasts, which closely resemble the chlorophyl bodies. In the first instance the change is more simple and under the  influence of light, in the latter light is not directly essential and the process is more complex, the starch formation beginning with intermediate substances – as asparagin, or glucose,  by conversion of the sugars in the cell sap.

Just as in the human organism, assimilation in plant tissue cannot take place except through solution, so the stored up starch is of no immediate service until it is rendered soluble.  In other words, it must be prepared in a way analogous to the digestion of food in animal tissues. This is done by the action of certain ferments manufactured by the protoplasm. These do not directly enter into the upbuilding of tissue themselves, but induce the change in the substance upon which they act. Chiefly by a process of hydration, in which several molecules of water are added, the insoluble bodies are rendered soluble, and are so carried in solution to various portions of the plant. Here they are rearranged as insoluble starch, to serve as the common storage tissue for sustenance. Thus it will be seen how very similar are the processes of assimilation in plants and animals, a marked characteristic between both being that the same elementary chemical substances are necessary in the upbuilding of their tissues, and  particularly that activity is absent where assimilable nitrogen is not present.

Several organic acids occur in plant cells, either free or combined, which are probably products of destructive metabolism, either from the oxidation of carbohydrates or from the decomposition of proteids. Liebig regarded the highly oxidized acids – especially oxalic, as being the first products of constructive metabolism, which, by gradual reduction, formed carbohydrates and fats, in support of which he referred to the fact that as fruits ripen they become less sour, which he interpreted to mean that the acid is converted into sugar. The probability, however, is that oxalic acid is the product of destructive metabolism, and is the final stage of excretion from which alkaloids are produced, while it is significant, when considering the Coca products, that acids may by decomposition be formed from proteid or may by oxidation be converted into other acids.

Oxalic acid is very commonly found in the leaf cells combined with potassium or calcium. It is present in the cells of  the Coca leaf as little crystalline cubes or prisms. Malic acid, citric acid, and tartaric acid are familiar as the products of various fruits. Tannic acid is chiefly found as the astringent property of various barks. Often a variety of this acid is characteristic of the plant and associated with its alkaloid. This is the case with the tannic acid described by Niemann in his separation of cocaine, which is intimately related to  the alkaloids of the Coca leaf, just as quinine is combined with quinic acid and morphine with meconic acid. It has been suggested that the yield of alkaloid from the Coca leaf is greater in the presence of a large proportion of tannic acid.

Tannin is formed in the destructive metabolism of the protoplasm, as a glucoside product intermediate between the carbohydrate and the purely aromatic bodies, such as benzoic and cinnamic acids, which are formed from the oxidative decomposition of the glucosides. In addition to these are found fatty oils, associated with the substances of the cell, and essential oils, to which the fragrance of the flower or plant is due, and which are secreted in special walled cells.  The resins are found as crude resins, balsams – a mixture of  resin and ethereal oil with an aromatic acid, and gum resins  – a mixture of gum, resin and ethereal oil. The ethereal oils include a great number of substances with varying chemical composition, having no apparent constructive use to the tissues, but, like the alkaloids, regarded merely as waste. Some  of these products serve by their unpleasant properties to repel animals and insects, while others serve to attract insects and thus contribute to the fertilization of the flower, so all these  bodies may be of some relative use.

The proteids of the plant are supposed to be produced  from some non-nitrogenous substance – possibly formic aldehyde – by a combination formed from the absorbed nitrates, sulphates and phosphates, in union with one of the organic acids, particularly oxalic. The change being from the less complex compound to a highly nitrogenous organic substance, termed an amide, which, with the non-nitrogenous substance and sulphur, unite to form the proteid. The amides are crystallizable nitrogenous substances, built up synthetically, or formed by the breaking down of certain compounds. They  are similar to some of the final decomposition products found in the animal body. Belonging to this group of bodies is xanthin, which Kossel supposed to be directly derived from nuclein, from the nucleus of the plant cell. But in whatever manner the amides are formed, it is believed they are ultimately used in the construction of proteid, and although this substance is produced in all parts of the plant, it is found more abundant in the cells containing chlorophyl. Proteids are found to gradually increase from the roots toward the leaves, where they are most abundant. This would seem to indicate that the leaf is the especial organ in which proteid formation takes place, and it is in this portion of the Coca plant that the excreted alkaloids are found most abundantly.

According to Schützenberger, the proteid structures are composed of ureids, derivatives of carbamide, and Grimaux considers they are broken by hydrolysis into carbonic acid, ammoniac and amidic acids, thus placing them in near relation with uric acid, which also gives by hydrolysis, carbonic  acid, ammoniac acid and glycocol. In animal tissues the last product of excrementition is carbamide – or uric acid, while the compounds from which proteids are formed in plants have been shown to be amides. It has been shown in the laboratory that the chemical products from the breaking down of proteids are also amides, with which carbonic acid and oxalic acid are nearly always formed. The presence of hippuric acid in the urine of herbivorous animals, the indol and the skatol found in the products of pancreatic digestion (Salkowski), together with the tyrosin nearly always present in the animal body, has led to the supposition that aromatic groups may also be constituents of the proteid molecule.

All of this is of the greatest interest in the study of alkaloid production in connection with the fact, which has been proved, that when a plant does not receive nitrogen from outside it will not part with the amount of that element previously contained – in other words, the nitrogenous excreta will not be thrown off. Boussingault thought the higher plants flourished best when supplied with nitrogen in the form of nitrates, though Lehmann has found that many plants flourish better when supplied with ammonia salts than when supplied with nitrates, and this has been well marked in the case of the tobacco plant.

Nitric acid may be absorbed by a plant in the form of any of its salts which can diffuse into the tissues, the most common bases being soda, potash, lime, magnesia and ammonia. The formation of this acid, attendant upon the electric conditions of the atmosphere, may be one source of increase of vigor to the native soil of the Coca plant, where the entire region of the Montaña is so subject to frequent electrical storms. Then Coca flourishes best in soils rich in humus, and various observers have remarked that nitrogen is best fixed in such a soil. An interesting point in connection with which is that the ammonia supplied to the soil by decomposition of nitrogenous substances is converted into nitrous, and this into nitric acid, by a process termed nitrification, occasioned by the presence of certain bacteria in the soil to which this property is attributed. Proof of this was determined by chloroforming a section of nitrifying earth and finding that the process on that area ceased. The absorption of nitrogen by the Coca plant and the development of  proteids is closely associated with the nitrogenous excreta from the plant, and the consequent production of alkaloids which we are attempting to trace.

The nitrogen of the soil, however induced, is transferred by oxidation into what has been termed the reduced nitrogen of amides which, in combination with carbohydrates, under appropriate conditions forms proteids, in which oxalic acid is an indirect product. Several observers consider the leaves as active in this process, because the nitrogenous compounds are found to accumulate in the leaf until their full development, when they decrease. This is illustrated by the fact that in autumn, when new proteids are not necessary to matured leaves, it accumulates in the protoplasm, from which it is transferred to the stem, to be stored up as a food for the following season’s growth.

It has been found that the nitrates, passing from the roots as calcium nitrate, are changed in the leaves by the chlorophyl in the presence of light with the production of calcium oxalate, while nitric acid is set free, and conversely, in darkness the nitrates are permitted to accumulate. This change is influenced by the presence of oxalic acid, which, even in small quantities, is capable of decomposing the most dilute solutions of calcium nitrate. The free nitric acid in combination with a carbohydrate forms the protein molecule, while setting free carbonic acid and water.

Cellulose, which we have seen is formed from protoplasm, is dependent upon the appropriate conversion of the nitrogenous proteid. When this formation is active, large amounts of carbohydrates are required to form anew the protein molecule of the protoplasm, and the nitrogenous element is utilized. When there is an insufficiency of carbohydrate material the relative amount of nitrogen increases because the conditions are not favorable for its utilization in the production of proteids, and this excess of nitrogen is converted into amides, which are stored up. When the carbohydrate supply to the plant is scanty in amount this reserve store of amides is consumed, just the same as the reserve fat would be consumed in the animal structure under similar conditions.

The relation between the normal use of nitrogen in plants is analogous to its influence in animal structure, while the final products in both cases are similar, the distinction being chiefly one in the method of chemical conversion and excretion due to the difference in organic function. Thus, although urea and uric acid are not formed in plants, the final products of both animals and plants are closely allied. We  see this especially in the alkaloids caffeine and theobromine, which are almost identical with uric acid, so much so that Haig considers that a dose of caffeine is equivalent to introducing into the system an equal amount of uric acid.

There are numerous examples, not only in medicinal substances, but in the more familiar vegetables and fruits, which illustrate the possibilities of change due to cultivation. The Siberian rhododendron varies its properties from stimulant to a narcotic or cathartic, in accordance with its location of  growth. Aconite, assafoetida, cinchona, digitalis, opium and rhubarb are all examples which show the influence of soil  and cultivation. Indeed similar effects are to be seen everywhere about us, certain characteristics being prominently brought forth by stimulating different parts of the organism, so that ultimately distinct varieties are constituted.  The poisonous Persian almond has thus become the luscious peach. The starchy qualities of the potato are concentrated in its increased tuber, and certain poisonous mushrooms have become edible. The quality of the flour from wheat is influenced by locality and cultivation. The tomato, cabbage, celery, asparagus, are all familiar examples which emphasize the possibility of shaping nature’s wild luxuriance to man’s cultured necessity.

The chemical elements which are taken up by a plant vary considerably with the conditions of environment, and the influence of light in freeing acid in the leaf has been indicated. These conditions necessarily modify the constituents of the plant. When metabolism is effected certain changes take place in the tissues, with the formation of substances which may be undesirable to the plant, yet may be medicinally serviceable. Such a change occurs in the sprouts of potatoes stored in the dark, when the poisonous base solania is formed, which under normal conditions of growth is not present in the plant. A familiar example of change due to environment is exhibited in the grape, which may contain a varying proportion of acid, sugar and salts in accordance with the soil, climate and conditions of its cultivation, nor are these variations merely slight, for they are sufficient to generate in the wine made from the fruit entirely different tastes and properties.

The Basic Nature Of Alkaloids

In view of these facts, it seems creditable to suppose that by suitable processes of cultivation the output of alkaloids may be influenced in plants, and such experiments have already been extensively carried out in connection with the production of quinine. When attention was directed to the scientific cultivation of cinchona in the East, it was remarked that when manured with highly nitrogenous compounds the yield of alkaloid was greatly increased. This is paralleled by the fact that when an animal consumes a large quantity of nitrogenous food the output of urea and uric acid is greater.

Alkaloids are regarded as waste products because they cannot enter into the constructive metabolism of the plant, though they are not directly excreted, but are stored away where they will not enter the circulation, and may be soon shed, as in the leaf or bark. Though, as indicating their possible utility, it has been shown experimentally that plants are capable of taking up nitrogenous compounds, such as urea, uric acid, leucin, tyrosin, or glycocol, when supplied to their roots. In some recent experiments carried out at the botanical laboratory of Columbia University, I found that plant metabolism was materially hastened under the stimulus of cocaine.

The influence of light in the formation of alkaloids has already been shown. Tropical plants which produce these substances in abundance in their native state often yield but small quantities when grown in hot houses, indicating that a too intense light is unfavorable, probably in stimulating a too rapid action of the chlorophyl, together with a decomposition of the organic acid. Some years ago the botanist. Dr.  Louis Errera, of Brussels, found that the young leaves of certain plants yielded more abundant alkaloid than those that were mature. Following this suggestion, Dr. Greshoif is said to have found that young Coca leaves yield nearly double the amount of alkaloid over that contained in old leaves gathered at the same time. In tea plantations the youngest leaves are gathered, but it has always been customary to collect the mature leaves of the Coca plant, and these have usually been found to yield the greatest amount of alkaloid. The probability is that the amount of alkaloid present in the Coca leaf is not so much influenced by maturity as it is by the period of its gathering.

As regards the temperature at which growth progresses most favorably, Martins  has compared each plant to a thermometer, the zero point of which is the minimum temperature at which its life is possible. Thus, the Coca shrub in its native state will support a range from 18° C. (64.4° F.) to  30° C. (86° F.), an influence of temperature which is governed by the proportion of water contained in the plant. It has been found, from experiments of cultivation, that Coca will flourish in a temperature considerably higher than that which was originally supposed bearable, though the alkaloidal yield is less than that grown more temperately. The life process of any plant, however, may be exalted as the temperature rises above its zero point, though only continuing to rise until a certain height is reached, at which it ceases entirely. In the cold, plants may undergo a similar hibernation as do certain animals when metabolism is lessened,  though long-continued cold is fatal, and frost is always so absolutely to Coca. The influence of temperature on metabolism tends to alter the relations between the volume of carbonic acid given off and the amount of oxygen absorbed.  Under a mean temperature these relations are equal, while in a lower temperature more oxygen is absorbed in proportion to the carbonic acid given off, and oxygen exhalation ceases entirely below a certain degree.

A relatively large proportion of water in a plant determines its susceptibility to climatic conditions. Thus freezing not only breaks the delicate parenchymatous tissues, but alters the chemical constitution of the cells, while too high a temperature may prove destructive through a coagulation of the albumen. The appearance of plants killed by high or low temperature being similar. Roots are stimulated to curve to their source of moisture, and their power for absorption is more active in a high than in a low temperature, but as absorption is influenced by the transpiration of the plant, it is less active in a moist atmosphere, unless the metabolic processes of the plant occasions a higher temperature than the surrounding air. Such activity would be increased by the heat of the soil about the roots, and is probably manifest in the Coca plant through the peculiar soil of the Montaña.

The elevation at which a plant grows has an influence upon the absorption by the leaf. Thus it has been observed that while a slight increase in the carbonic acid gas contained in the air is favorable to growth, a considerable increase is prejudicial, while an increase or diminution of atmospheric pressure materially influences plant life. In some tropical countries Coca will grow at the level of the sea, provided there is an equable temperature and requisite humidity. Although in Peru Coca flourishes side by side with the best  coffee, it will not thrive at the elevations where the coffee plant is commonly grown in either the East or West Indies. In Java, where experiments have been made in cultivating Coca, it has been stated that there is no perceptible difference in the alkaloidal yield due to the influence of elevation, while in the best cocals of Peru it is considered that the higher the altitude at which Coca can be grown the greater will be the alkaloidal yield. This is possibly effected by similar influences to that governing the aromatic properties developed in  the coffee bean, which have been found more abundant when coffee is grown at an elevation, yet without danger of frost.  This may be attributed to slower growth and a consequent  deposit of nitrogenous principles instead of their being all consumed through a rapid metabolism.

It is therefore evident that as these several physical conditions have a marked bearing upon the life history of all plants, the more limited the range for any of these processes in any particular plant, the more it will be influenced. Thus in an altitude too high, the leaf of the Coca plant is smaller and only one harvest is possible within the year, while in the lower regions where the temperature exceeds 20° C. (68° F.)  vegetation may be exuberant, but the quality of leaf is impaired. The electrical conditions of the atmosphere, it has been shown, have an important bearing upon the development of Coca, through the influence of the gases set free in the atmosphere and the possible slight increase of nitric acid carried to the soil.

It was thought by Martins that the mosses and lichens which are found upon the Coca shrubs were detrimental to the plant through favoring too great humidity. In the light of our knowledge on the development of alkaloids, however, it has seemed to me that here is an opportunity for very extended experimentation, as may be inferred from a reference to the alkaloidal production of cinchona. At first efforts were made to free the cinchona trees from the lichens and mosses which naturally formed upon them; but it was discovered accidentally that those portions of the trees which nature had covered in this manner yielded an increased amount of alkaloid. When cinchona plantations were started in Java, experiments made upon the result of this discovery prompted a systematic covering of the trunks of  the trees artificially with moss, which was bound about them to the height from which the bark would be stripped. At  first very great pains was taken to collect just an appropriate kind of moss, which it was supposed from its association with the tree in its native home would be essential, but later experiments proved that any form of covering which protected the bark from light increased this alkaloidal yield. So  that to-day this process, which is known as “mossing,” is one of the most important in the cultivation and development of cinchona.

A Source Of Profound Confusion

The chief interest of Coca to the commercial world has centered upon its possibilities in the production of the one alkaloid, cocaine, instead of a more general economic use of the leaf. Because of this, much confusion of terms has resulted, for chemists have designated the amount of alkaloids obtained from the leaf as cocaine, although they have qualified their statement by saying that a portion of this is un-  crystallizable. Numerous experiments have been conducted to determine the relative yield of cocaine from the different varieties of Coca, and when uncrystallizable alkaloids have been found the leaf has been condemned for chemical uses.  It will thus be appreciated how a great amount of error has been generated and continued. The Bolivian or Huanuco variety has been found to yield the largest percentage of crystallizable alkaloid, while the Peruvian or Truxillo variety, though yielding nearly as much total alkaloid, affords a less percentage that is crystallizable, the Bolivian Coca being set apart for the use of the chemists to the exclusion of the Peruvian variety, which is richest in aromatic principles and best suited for medicinal purposes. As a matter of fact, the Peruvian Coca is the plant sought for by the native users.

There is not only a difference in the yield of alkaloid from different varieties of Coca, but also a difference in the yield from plants of one variety from the same cocal, and it would seem possible by selection and propagation of the better plants to obtain a high percentage of alkaloid. At present there is no effort in the native home of Coca toward the production of alkaloid in the leaf through any artificial means.  Regarding the quality of alkaloid that has been found in the different plants, the Peruvian variety has been found to contain equal proportions of crystallizable and uncrystallizable alkaloid, while the Bolivian variety contains alkaloids the greater amount of which are crystallizable cocaine. Plants which are grown in conservatory, even with the greatest care, yield but a small percentage of alkaloid, of which, however, the uncrystallizable alkaloid seems more constant while the relative amount of cocaine is diminished. In leaves grown at Kew .44 percent, of alkaloid was obtained, of which .1 percent, was crystallizable. From experiments of Mr. G. Peppe, of Renchi, Bengal, upon leaves obtained from plants imported from Paris, it was found that leaves dried in the sun yielded .53 per cent, of alkaloid, of which .23 per cent was  uncrystallizable. The same leaves dried in the shade on cloth for twenty hours, then rolled by hand, after the manner in which Chinese tea is treated, then cured for two and a half hours and dried over a charcoal fire and packed in close tins, yielded .58 per cent, of alkaloid, of which .17 per cent, was  uncrystallizable.

It is probable that each variety of Coca has a particular range of altitude at which it may be best cultivated. The Bolivian variety is grown at a higher altitude than Peruvian Coca, while the Novo Granatense variety has even been found to thrive at the level of the sea. Among Coca, as among the cinchona certain varieties yield a large proportion of total alkaloids, of which only a small amount is crystallizable. The Cinchona succirubra yields a large amount of mixed alkaloids, but a small amount of quinine, while Cinchona Calisaya yields a smaller amount of mixed alkaloids and a large amount of crystallizable quinine. A few authors who have referred to the alkaloidal yield of Coca leaves have casually remarked that the plants grown in the shade produce an increased amount above those grown in the  sun, which would appear to be paralleled by the formation of chlorophyl and the production of proteids, both of which have so important a bearing upon the metabolism of the plant and the final nitrogenous excretion.

This subject is one full of interest, yet so intricate that it has not been possible for me to elaborate the suggestions here set forth in time to embody my investigation in the present writing, though I hope to present the result of my research at no very distant date. It would seem that sufficient has been shown, however, to indicate the possibility of modifying plant metabolism under appropriate conditions of culture so as to influence the development of the alkaloidal excreta. The comparisons between plant and animal life may have proved of sufficient interest to enlist attention to the higher physiology in which will be traced the action of Coca.