436 DESMIDS OF THE PACIFIC COAST. 



mavium rJiombusoides I consider a new species. The semi- 

 cells are in the form of a rhombus — four-sided — unlike sex- 

 angulare, which has six sides, as its name implies. It is 

 besides a larger plant than the latter. 



I was glad to see Staurastrum xiphidiophorum, described 

 by me in Bull. Torr. Glub, occurring frequently in the vial. 

 It has been hitherto found only in Minnesota, and differs 

 somewhat from the type in not having quite so many spines 

 (daggers) . 



Staurastrum Brasiliense, Nord. var. triquetrum. — This 

 (the typical plant) was originally found in Brazil, and was 

 described as usually four -sided, sometimes five -sided. 

 Your form, although only three-sided, is so like it that I 

 propose to call it var. triquetrum. 



The ladies to whom we are indebted for these specimens 

 are to be heartily congratulated upon the success of their 

 researches. Never did I see a richer collection of Desmids, 

 and it afforded me much gratification. I have been trying 

 the past ten years to get fresh-water alg?e from your State, 

 but always failing, I began to think that California had 

 none, however rich the marine forms might be. 



I might have supposed that the forms of Desmids, etc., 

 found on your coast would differ from ours much more than 

 they do, but I was surprised a few days since to observe 

 by a list published in England how like our own those of 

 Japan are. 



The following fresh -water algae, not belonging to the 

 Desmidiacece, were also found in the vial: 



Pediastkum Boryanum, Turp. 

 Pediastrum forcipatum, a. Br. 

 Pediastrum Ehrenbergii, a. Br. 



