MICHIGAN ACADEMY OF SCIENCE. 197 



from year to year. The roots may not be as large or of as fine quality as 

 those profUicefl in China, but the obtaining of a finer drug material is doubt- 

 lessly merely a matter of a better understanding of the cultivation of the 

 plant. The u.^e of fertilizers and a certain amount of protection may be 

 required. 



DIENNIAL PLANTS. 



There are quite a number of medicinal plants that do not yield drugs 

 imtil the second year, such as some forms of henbane, caraway, etc. Such 

 plants will need some sort of covering or protection so that the loss from 

 freezing would be reduced to the minimum. Again it may be that some of 

 these plants will be found to be valuable in the first year. The studies made 

 in the United States have proven this to be true of digitalis and in fact, the 

 digitalis leaves of the first year's plants grown at the University of Michigan 

 were three times as strong as that of the official article. This was not true 

 however of henbane, but this is in part due to the fact that the leaves of hen- 

 bane were badly attacked by the potato beetle, which consumed the fleshy 

 portion between the veins in which the greater part of the active principle 

 resides. 



There is another possibility in the case of plants like caraway which do 

 not ordinarily set fruit or seed until the second year. It is possible by starting 

 the plants early enough in the greenhouse and planting them outdoors very 

 early in the Spring to crowd two seasons into one. AVe did not succeed in 

 doing this with caraway this year, but quite a number of biennial plants bore 

 fruits in the first summer here. This offers very great possibilities in the 

 matter of preserving the fruits of this type of plant and cultivating it to 

 better advantage. 



PLANT SELECTION AND BREEDING. 



It is well known to nearly everyone how our agricultural crops have been 

 improved by selecting and breeding. Owing to the minor importance of 

 medicinal plants as compared to farm products not much has been done in 

 scientific selection. More attention has been given until now on the ix)ssi- 

 bilities of the use of chemical fertilizers. A priori we can exi)ect the same 

 results in the study of medicinal plants as we have seen with other plants 

 which have been studied scientifically. The experiments made with cinchona 

 in Java will be paralleled with other plants. Here trees running low in alka- 

 loid have been by selection and hybridization made to yield as high as 15% 

 of alkaloid. Furthermore, it has been possible to study them witli the view of 

 increasing the most desirable of these alkaloids, quinine. It will be found 

 that one can accomplish almost anything reasonable if he will but start the 

 experiment and continue until he achieves his result. At this point it also 

 should be staled that climate and soil may have .some influence, but from 

 our experiments this summer we must either conclude that these factors are 



