32 STOCK-POISONING PLANTS OF MONTANA. 



the case of herbaceous plants, but with some, such as aconite, purple 

 larkspur, poison camas, and many bulbiferous plants closely related 

 to the last, it is earlier, the leaves of some of them having entirely 

 dried up before the plants have flowered. In these cases the leaves 

 would naturally be most active physiologically if eaten before the 

 plants blossomed, and might be practically inert at other times. 

 Such seems to be the case with the purple larkspur. The taste of the 

 leaves, as well as the results of our experiments and the observations 

 of others, indicate that the root as well as the leaves is more poison- 

 ous before the flowering time than afterwards. The -^ame is true also 

 of the leaves of the tall larkspur. In both cases the leaves are fre- 

 quently in the succulent condition after the flowers have expanded. 



A very interesting and instructive investigation of the formation 

 and occurrence of poisonous alkaloids in foliage has recently been 

 carried out in the case of the cinchona alkaloids in cinchona leaves by 

 Dr. J. P. Lotsy ^ in Java. The author showed that the quantity of 

 alkaloids varied greatly in the leaf as taken by day or night and on 

 sunshiny or cloudy days, being most abundant in the first instance in 

 each case. He showed also that these alkaloids are formed in the 

 leaves during the day and are almost wholly deposited in the branches 

 or bark at night. If gathered in the early morning, therefore,, cin- 

 chona leaves would be practically inert, while if gathered in the 

 evening, especially on a sunshin}^ day, the}' would be in their most 

 active state. 



It has been shown that the location of alkaloids and other toxic sub- 

 stances in plants is not always the same even in similar organs. These 

 are sometimes to be found in the most rapidly growing parts of the 

 plants, as in the white sprouts of potatoes, and again the}-^ are to be 

 found in parts which have been fully developed, as in the case of 

 sapotoxin in corn cockle {Agrostenihia githago). In both of the above 

 cases the remaining portion of the organ is edible. Barth" has shown 

 that in aconite seeds the central parts contain most of the aconite, while 

 the seed coats are free from it; in the calabar bean {Physostigma i^en- 

 enosa) the very poisonous alkaloid, eserine or physostigmine, is found 

 in the cotyledons; in the seeds of jimson weed (Datura ■stramoniuvi), 

 black henbane (Hyoscyam/us nige7'), and belladonna (Atrajx/. helladcmna) 

 the alkaloids are located chiefl}- in the layer beneath the epidermis. 

 The epidermis itself and the seed covering is in each case free from 

 alkaloids; in nux vomica seeds, strychnine and brucine are found in 

 the endosperm cells, but l)rucine alone occurs in the embryo. In 

 jimson-weed seeds the quantity of alkaloids in unsprouted seeds was 

 found to be 15 times as great as in sprouted seeds. In growing col- 

 chicum the percentage of alkaloid is ver}^ large in the growing tips 

 and comparatively low in the lower part of the bulb. The first year's 



' Mededeeling uit ' Rlands Plantentuin, vol. 3B. 1899. 

 •^Merck's Market Report, vol. 8, pp. 306-307. 1899. 



