NEW CYANOPHYCE^. 119 



sule. From specimen in Herb. Columbia Coll., collected at 

 Byron Springs by Prof. Greene. 



Fig. 17. Base of replum and mature dehiscent internal 

 pod, from specimen in Herb. Gray, collected at Byron, by 

 Mrs. Braudegee. The outlines of the two seeds show 

 through the valves. 



Fig. 18. Pod from the same plant with 3 valves, 2 of them 

 already removed, a. Remaining valve, b. Internal cap- 

 sule, unusual in arising from one of the placentae instead of 

 being axial. 



Fig. 19. Capsule of Draba alpina, L. with 4 valves, 4 

 placentae, and containing a 2-valved internal capsule. Re- 

 drawn from figure by Peyritsch in Pringsheim's Jahrbuch, 

 vol. viii. t. 7. 



Figures 1 to 18 drawn from nature by the author. 



Gray Herbarium, Cambridge, Mass., April 18th, 1896. 



NEW CYANOPHYCE^. 



By Frank S. Collins. 



ANABiENA CATENULA (Kuetz.) Born. & Flah. var Americana, 

 n. var. Spores 30-60 fx long, strictly cylindrical. 



The typical form, with spores 16-30 jx long and constricted 

 at the middle, occurs throughout Europe, but has not 

 yet been found in America; the difference between our 

 form and the European seems to be constant, but not 

 of specific value. The trichomes vary from 5 to 8 yu 

 in diameter, and the cells vary, probably according to age 

 and activity of cell division, from cylindrical with rounded 

 ends and about twice as long as thick, to compressed spheri- 

 cal with length slightly less than the diameter. The full range 

 of variation, both as to size and shape, may be seen in the 

 same collection, and when extreme forms come side by side, 

 they would seem to be distinct species; all intermediate 



