Baath AD 
1901] CURRENT LITERATURE 223 
then can be the value of this classification, out of sympathy with the purposes 
of morphology on the one hand and the spirit of natura] history on the other? 
The illustrations are photographs of mounted algae on cards, and in some 
cases of preparations slightly magnified. While many are clear others seem 
to the writer quite valueless as a means of identification and unworthy of the 
book. Although the color of the specimen would help in this mechanical 
matching of mounts with figures, nevertheless there is sure to be much con- 
fusion. For example, how is Enteromorpha clathrata to be distinguished 
from certain Cladophoras? The figure of Ectocarpus viridis might do for 
several other species, the Callithamnia are quite impossible, and Polysiphonia 
fastigiata is certain to be confused with Sphacelaria. 
One occasionally finds statements that lead to the belief that the author 
is quite untrained in natural history. Thus, on page 29 is the — 
“Ectocarpus Hooperi, a species of Ectocarpus ie described by Mr. Hooper.” 
This does not seem to be a fact, and the impression conveyed that naturalists 
name species after themselves is an implication of conceit far from being 
warranted by the conduct of these modest members of society. 
The book has yet to be written that will tell the natural history of sea- 
weeds with the charm of manner shown inthe style of Miss Margaret Morley. 
And until such a treatment appears, it is much better that the amateur col- 
lector and observer of marine algae read Murray's /ntroduction to the study 
of sea-weeds, a simple and very interesting account, and one thoroughly 
grounded in science.— B, M. Davis 
NOTES FOR STUDENTS. 
PROFESSOR ARNOLDI? has taken up the somewhat incomplete work of 
Shaw, and has made a careful study of the development of the endosperm of 
Sequoia sempervirens. Free nuclear division takes place in the usual manner 
in an evenly distributed peripheral layer of protoplasm, but very soon there 
is a denser accumulation of protoplasm at the lower end of the sac. When 
the formation of walls begins, three regions of the endosperm may be dis- 
tinguished, the upper, the lower, and the middle. The upper, and particu- 
larly the lower, develop faster than the middle, so that the ends of the sac 
become filled with a solid tissue while the nuclei are still almost free in the 
middle portion. Each nucleus of the middle portion now becomes sur- 
rounded by a wall which is open on the inner side: the walls grow inward 
and when the center is reached, walls are formed at the inner ends of the 
cells. The nucleus now begins to divide, and each of these cells (“alveoli”) 
becomes divided into several cells. Archegonia are formed only from these 
*ARNOLDI, W.: Beitrage zur Morphologie einiger Gymnospermen. I. Die Ent- 
wickelung des Endosperms bei Seguota sempervirens. Bull. des Natur. de Moscow. 
Pp. 1-13. Pls. 7-8. 1890. 
