270 BOTANICAL GAZETTE [September 



8-io). 



seem the same as for Ascophyll 



After this the account differs, for the coming in of walls was 

 observed in many cases. For instance, a rather unusual case is 

 the occurrence of seven nuclei, and the division into three parts by 

 two horizontal walls (fig. n). The coming in of a vertical wall 

 after the formation of a single horizontal one is also found (fig. 12). 



most usual situation seems 



the nuclei and the plastids (fig. 13). Here 

 groups can be seen and also a seventh nu 



Rarely (fig. 14) 



four eggs are formed and eight nuclei are present. This may be a 

 situation immediately preceding that presented in fig. 15, or the 

 walls shown in fig. 13 may have disintegrated, leaving only the 

 primary walls. No spindles were seen to account for the formation 

 of the walls. They may have been formed by cleavage as does 

 happen among certain of the algae and fungi. 



W 



genesis remain 

 ae. it seems cer 



to be investigated in 



condition followed by eight functioning eggs is primitive, and that 

 most of the genera which form less than eight eggs pass through 

 this stage. 



Hormosira 



final 



condition is reached by the breaking down of four immature eggs 

 rather than of four free nuclei. Such a condition is safely inter- 

 preted as less removed from the Fucus condition than forms in 

 which the 4-nucleate stage is reached by the breaking down of 

 free nuclei. 



much indebted to Dr. C. J 



whose direction the work was 

 the photographs in the text. 



University of Chicago 



J 



LITERATURE CITED 



1. Bower, F. O., On the development of the conceptacle in the Fucaceae 



Quar. Jour. Mi,. Sci. 20:36-49 



Uber Aufbau und Ent 

 >:4-6. pi. I. 1896-1897. 



Bibli- 



