Sy 

1901 | CURRENT LITERATURE 133 
NOTES FOR STUDENTS. 
IN TWO PAPERSS Dr. Bessey states that some recent observations of his 
have lead him to think that the greater portion of the state of Nebraska is 
capable of supporting a tree vegetation. He claims that the absence of trees 
is due to the prairie fires, and that now wherever given a chance the tree area 
of the state is spreading. — H. N. WHITFORD. 
ACCORDING TO MIYAKE ® the majority of the leaves of Japan evergreens 
are found to contain more or less starch in winter, only one third of the 
species being devoid of it altogether. The starch content in winter, how- 
ever, is considerably decreased; this decrease begins in November, the 
minimum of starch is found in January, and the amount increases again in 
February. The author also shows that starch is actually manufactured in 
winter, though much less than in summer.—H. C. CowLEs. 
NEMEC asserts’ that in certain plant parts, ¢. g., the root, where transmis- 
sion of a stimulus occurs, there are embedded in a special plasma fibrils, the _ 
clusters of which, by proper staining, may be made easily visible with mode- 
rate magnification. These fascicles correspond on opposite sides of the 
partition walls and presumably are continuous or at least in contact through 
it. Experiment has shown that conduction of a stimulus is more rapid in the 
direction of these fibrils than across them, and tha: after their degeneration 
‘this difference in rate disappears. The perceptive region of the root, he 
declares, lies mostly in a special group of cells in the root cap. These are 
characterized by a very fluid plasma, and permanent starch grains which 
easily sink through it to rest on the ectoplasm. “Fibrils extend from these 
cells to the region of curvature. In some roots this group of cells becomes a 
special organ, which may be compared in principle with the organs of equilib- 
rium (vesicles with statoliths) in certain lower animals. (Cf. Noll, rev. in 
Bor. Gaz. 30: 134. Igoo0.)—C. R. B. 
Mr. JAmes A. TERRAS, of Edinburgh, has examined the conditions 
under which the winter buds of Aydrocharis Morsus-rane germinate. This 
plant propagates itself by buds, formed at the extremities of the subaqueous 
runners, in which is stored an abundant supply of reserve proteid, apparently 
a fluid albumin. The autumnal buds separate as soon as mature and sink to 
the bottom, where they rest till the following spring, or longer if covered by 
mud to the depth of two or three centimeters. It seems that this cover is 
effective merely because it cuts off the light, any other opaque screen like- 
wise preventing germination. Indeed if merely much shaded the buds do 
*The forest and forest trees of Nebraska. Reprint from Report of Nebraska 
Board of Agriculture, pp. 79-102. 1899. 
€ natural spreading of timber areas. Forester 6: 240-243. 1900. 
* Bot. Mag. 14: 44-49. 1900. 7 Biologisches Centralblatt 20: 369. 1900. 
