IQI2] 



YA MA NO UCHI—C U TLERIA 



447 



there are also tufts of hairs. Any part of the frond in vigorous 

 growth is favorable for the study of vegetative mitosis, but details 

 are more easily and definitely followed in the hairs and in the super- 

 ficial layer of the thallus. 



The cells in these regions are full of plastids, with usually a single 

 nucleus in the center. The nucleus in the resting stage is very 



Fig. 



i. 



Cutleria multifida: portion of a thallus with a number of filaments and 



young male gametangia. 



small, generally about the size of the plastids or slightly larger 

 (% s - 1 y 5, *6, 53). The network is so fine that it is hard to recognize 

 much chromatin in it. Neither centrosome nor central bodies with 



without radiations seem 



becomes 



three or four times the diameter of 1 

 conspicuous structure within the cell. 



growth 



