1905] CURRENT LITERATURE 157 
sidered are the zoospore, sperm, egg, spore mother cell, coenocyte, and coenoga- 
m rms and eggs are compared with the zoospores with which they are 
phylogenetically related. After considering the literature of the blepharoplast, 
the writer is inclined to the view that it does not represent a centrosome. The 
statement that the synergid may possibly represent portions of a reduced arche- 
gonium is somewhat surprising. The author believes that there is no qualitative 
reduction during the mitoses in the spore mother cell. Pallavicinia receives , 
icular attention. About one hundred and twenty papers are cited in the 
bibliography of this section.—C. J. CHAMBERLAIN. 
SHREVE’? has investigated the morphology of Sarracenia purpurea. The 
microsporangium passes the winter in the mother cell stage, a two-layered tapetum 
is developed, the reduced number of chromosomes is twelve, and the tube and 
generative nuclei appear before the shedding of the pollen. In the megaspor- 
angium the integument is single, no parietal cell is cut off, and a linear series of 
four spores usually appears, although there are variations in number and arrange- 
ment. The functional megaspore (innermost one) destroys the overlying nucellar 
layer at the micropylar end and comes to lie directly against the integument. 
The endosperm has developed extensively when the embryo is two-celled. In 
germination the cotyledons act as haustoria, ‘(and survive as simple liguliform 
leaves bearing chlorophyll.””—J. M. C. 
FritscH?° claims that the cells of the Cyanophyceae are provided with a 
delicate cell immediately investing the protoplast in addition to the sheath, which 
is characteristic of many forms or of mucilaginous envelops. The inner invest- 
ment is regarded as a modified plasma membrane of a-viscous gelatinous nature. 
The outer envelop is called the cell-sheath, and is believed to be a modified inner- 
most layer of the external mucilaginous investment. This view is quite different 
from that of most algologists, who regard the sheath as directly derived from the 
protoplast. Frirscx also believes that the intercellular protoplasmic connections 
described by other autbors are due to peculiarities in the staining of the gelatinous 
partitions between the cells.—B. M. Davis. 
THE LAMINARIACEAE pass through several phases in their life histories, 
Which have been grouped as the embryonal and the post-embryonal. The 
embryonal stages include the periods up to the time when the simple laminarioid 
frond is developed; and the post-embryonal the later changes leading to the adult 
condition which is so various in the different genera. Considerable attention is 
kely to be given to the post-embryonal stages of development, which promise 
to throw much light on the problems of relationship. YENDO’s work in 1902-3 
on Echlonia, Eisenia, and Hedophyllum has recently been supplemented by an 
s 19 SHREVE, Forrest, The development of Sarracenia purpurea L. Johns Hopkins 
nv. Circ. No. 178. pp. 31-34. 1905. 
*° Fritscu, K., Studies on the Cyanophyceae. II. Structure of the investment 
~ spore-development in some Cyanophyceae. Beih. Bot. Centralbl. 18: 194-214. 
ZT. 1905. A 4 ; 
