1921] Lewis & Taylor,— Notes from Woods Hole— 1921 253 



spores. Considerable material was obtained by the kindness of Dr. 

 Alice M. Russell, and some was sent to Dr. Gilbert M. Smith, who 

 identified the form as Anabaena spiroides var. crassa Lemm., noting 



^ <D 



Fia. 1. Anateana spiroides var. crassa. A, Trichome showing three heterocysts 

 but no spores. X 300. B, C, D, Portions of trichome showing spores and heterocyst. 

 X 050. 



however that the spores of the Nantucket material are round, whereas 

 those of this variety of Anabaena spiroides are typically elongate. 

 The measurements of the Nantucket form are: trichome 1 1 .5[j. average 

 diameter, heterocysts 13[jl diameter, and spores thick and smooth- 

 walled, diameter 22jx. Dr. Smith has reported Anabaena spiroides 

 var. crassa as occurring in Wisconsin lakes. — W. R. Taylor. 



Mougeotia tenuis (Cleve) Wittrock. This distinct form was found 

 with zygospores in a small pond on Pasque Island July 6, 1921. 



Mougeotia parvula Hassall. Abundant material of this speeies in 

 all stages of conjugation appeared in a drinking fountain in Woods 

 Hole, July 1921. 



Bryopsis hypnoides Lamx.- — In a specimen of Bryopsis hyjmoides 

 Lamx., collected from a float in the harbor near the laboratory, a great 

 many of the branches were found to contain gametes. All of the 

 protoplasm of the branch goes into the formation of the gametes, which 

 escape through several pores in the cell walls. The passage out was 

 moderately rapid. On the slide under the microscope, the female 

 gametes soon settle down and become motionless, whether fertiliza- 

 tion occurs or not. The males are more active, settling down later. 

 Some branches contained both male and female gametes. In such 

 cases the number of female gametes is greater. Other branches ap- 

 parently produce only one kind. 



The male gametes are very small and biciliate, the cilia being of 

 equal or possibly subequal length. The chloroplast is massed in the 



