382 BOTANICAL GAZETTE [NOVEMBER 
what regularly scattered spots. Later, with or without association of 
hairs, there are produced short filaments which afterward bear male 
gametangia. Both the filaments and the hairs arise from superficial 
cells of the thallus. 
One of the superficial cells commences to grow more vigorously 
than the rest and a typical nuclear division takes place. Two or 
more subsequent divisions result in a short filament of three or more 
cells, the terminal one of which is destined to be a male gametangium 
initial, whose nucleus becomes considerably larger than is common in 
cases of vegetative mitosis. The mitoses which take place up to the 
formation of the male gametangium initial are typical and the number 
of chromosomes is 24. 
The details of nuclear division are much more easily and distinctly 
followed in the gametangia. During the prophase of the first division 
in the gametangium initial, even before the segmentation of chromo- 
somes, the nucleus is marked by two distinct kinoplasmic accumula- 
tions at the poles, and their position indicates the axis of the division. 
The formation of the cell plate between two daughter nuclei is some- 
times much more delayed than in cases of vegetative mitosis. 
Following the first division in the gametangium there are several 
cell divisions, the walls being somewhat perpendicular to one another; 
as a result there is formed the well-known male gametangium of 
Cutleria, composed of a great number (sometimes as many as 200) 
of mother cells, regularly arranged in vertical and horizontal tiers. 
During all of these successive divisions 24 chromosomes appear. 
The nucleus, cytoplasm, and plastids in the mother cell undergo 
a certain peculiar change, and the whole contents of the mother cell 
enter into the formation of a male gamete. After the maturity of 
the gamete a tiny hole is developed in the peipeet wall of the 
mother cell, through which the gamete escapes. 
FORMATION OF FEMALE GAMETES.—The formation of tufts of hairs 
and of filaments bearing female gametangia is similar to that already 
described for the male plant. The structure of the cells of the super- 
ficial layer is apparently like that of the male plant, and so far as the 
development of hairs and the behavior of nuclei are concerned, there 
seems to be no distinction; but the difference is remarkable when the 
superficial cell which is destined to form a female gametangium begins 
