- 1904] CURRENT LITERATURE 
317 
_ ophyte proceeding as usual, so far as parietal placing and centripetal growth 
are concerned. The method of forming the permanent endosperm tissue is 
remarkable, and is either unusual among gymnosperms or has escaped observa- 
tion. The primary endosperm cells, that is those open towards the center of the 
sac, elongate inward, and free nuclear division proceeding they become multi- 
nucleate. Then comes a stage when “hundreds of the free nuclei divide about 
the same time,” but no cell plate is formed between the daughter nuclei, the 
kinoplasmic fibrils extending between them increasing in number and curving 
outwards on all sides until both nuclei are completely surrounded by a sheath 
of fibrils which fuse, thus forming an investing membrane. This method of free 
cell formation goes on throughout the whole of the prothallium except in the 
region of the archegonium initials, the cells becoming crowded and thus resem- 
bling ordinary tissue composed of binucleate cells. After this tissue has been 
organized nuclear division with cell plates proceeds in the usual way. 
The archegonium initials were observed about May 25, and eight to fifteen 
archegonia are organized into a complex. invested by a common layer of jacket 
cells. The neck cells are usually four in number, and just before fertilization 
the nucleus of the central cell divides into ventral canal and egg nuclei, without 
the formation of any separating membrane. Only one male cell enters an egg, 
two 88s thus being fertilized from one tube, and the male nucleus is liberated 
from its cytoplasmic sheath only after the male cell has become imbedded in the 
°2 cytoplasm. 
tiers of cells and four free nuclei. The cells of the upper tier elongate 
g and tortuous suspensor, and one or several embryos may be devel- 
Single egg. The estimated but not definitely counted number of 
mes was nine or ten for the gametophyte and eighteen or twenty for the 
sporophyte. phyt & 
The Seneral conclusion is reached that the structures of Cryptomeria are 
distinctly of the Cupresseae type—J. M. C. 
