1916] CURRENT LITERATURE 323 
plant is traced to a difference in physiological stability of their respective 
protoplasms. In animals the stable molecules which form nervous tissue 
accumulate in spite of the high metabolic rate, while in plants the degree of 
physiological stability is low, and the high metabolic rate of the apical point 
may mobilize the whole substratum. It is only in regions of lower rate that the 
accumulations of visible structure can occur. In this contrast we see one of 
the fundamental differences between the two classes of organisms 
The reader is favorably impressed by the thoughtful ie and Stuminntiie 
manner in which the philosophical discussion proceeds. The dynamic concep- 
tion of individuality presented in this work seems so reasonable, and the mar- 
shalled evidence is so clear and convincing, that it is bound to exert a profound 
influence on biological thought and theory. The author modestly states that 
this conception is “manifestly far from being a complete solution of the problem 
of organic individuality.” It is an excellent working hypothesis, however, 
Suggests many lines of experimental approach toward a final schitian; and offers 
an attractive substitute for the unsatisfactory vitalistic conceptions which 
have held until now so prominent a place in our philosophy of organic life — 
Cuartes A. SHULL. 
NOTES FOR STUDENTS 
Linkage and crossing-over in oats.—SURFACE’ is continuing in Genetics a 
series of studies in oat breeding of which two former papers have appeared in 
the Annual Report of the Maine Agricultural Experiment ne . will 
be very gratifying indeed if this new journal makes so stron 
to geneticists that work of high grade will no longer be buried with ae shee 
eral literature as that which makes up the bulk of nearly every station report. 
In crosses between strains of wild and cultivated oats (Avena fatua and 
A. sativa), SURFACE has studied particularly the inheritance of qualitative 
characters in the flowering glumes. The base of the fertile floret in the wild 
oat is characterized by a broad callus associated with ease of abscission from 
the spikelet, whereas the lack of the callus in the cultivated oat is associated 
with persistence of the floret. First generation hybrids present the callus in 
an intermediate condition, and in subsequent generations typical Mendelian 
Segregation takes place. There are, ieee three types of bases, called, for 
short, “cultivated,” “intermediate,” and “wild.” Perfectly correlated with 
the “cultivated” base are the almost complete absence of awns on the lower 
flowering glume, their complete absence from the upper flowering glume, the 
absence of pubescence from the rhachilla, the slight pubescence at the base of 
the first floret, and its complete absence at the base of the second floret. Con- 
versely, the “wild” base is perfectly correlated with the presence of well de- 
? SURFACE, FRANK M., Studies on oat breeding. III. On the inheritance of cer- 
tain glume directo in the cross Avena fatuaXA. sativa var. Kherson, Genetics 
1: 252-286. 1916, 
