DEPARTMENT OF BOTANICAL RESEARCH. 69 



and growth, it was necessary to undertake their preparation. The 

 courtesy of Professor G. N. Lewds in extending the hospitality of the 

 chemical laboratory of the University of California made it possible 

 to carry on this work during the months of June, July, and part of 

 August. Under the circumstances the best method proved to be the 

 hydrolysis of proteinaceous material and separation of the amino-acid 

 esters by fractional distillation under high vacuum. Excellent jdelds 

 of glycocoll and alanin were obtained from Japanese raw silk. Some 

 difficulty was encountered in obtaining high-grade gelatine, as the 

 poorer grades yield very unsatisfactory products. However, from this 

 source and from the silk a very good supply of glycocoll, alanin, leucin, 

 and crude prolin was obtained which will meet immediate requirements. 



PHYTOGEOGRAPHY AND ECOLOGY. 



Biological and Physical Factors affecting Plants in New Habitats, by 



D. T. MacDougal 



The plan of the implied investigations included the estabhshment of 

 small experimental areas in four places in which the environmental 

 complexes were widely different, the introduction of species from out- 

 side localities, and the exchange of species native to the localities of 

 the experimental plots. 



Three of the experimental areas were in connected physiographic 

 series by which one was in the coniferous forest on the crest of a range, 

 a second in the mid-slopes among the oaks, and the third in the desert 

 valley at the foot of the range. This arrangement was one by which 

 the tests might be expected to jdeld dh-ect information on the dissemi- 

 nation of the local species and on the barriers to distributional move- 

 ments. In addition, all three were used to test the beha\dor and sur- 

 vival of species from distant regions in which they were habituated to 

 different environmental conditions. The fourth plantation was located 

 near the shore of the Pacific Ocean in a cool, equable, foggy coastal cli- 

 mate, at a distance of nearly 1,300 km. from the first three planta- 

 tions. The observations and experiments in the coastal plantation 

 were directed chiefly to the study of the effects of the long and cool 

 growing season on plants from deserts, from mountain summits, and 

 from eastern America. 



The records of beha\nor of the separate species have been kept with 

 adequate accuracy from the time of their introduction, which in some 

 cases extends over a period of 14 years, and the duration of the tests 

 is illustrated by the fact that trees of Juglans now producing nuts were 

 introduced as nuts in the beginning of the experiments. 



The observations have been carried to a stage in which a compre- 

 hension of chmatic complexes as barriers has been gained, and a conclu- 

 sive demonstration of an animal barrage has been found. The relative 

 value of seeds and of various types of resting shoots has been notably 



