ABCHEE ON MICBASTERIAS MAHABULESHWABENSIS (HOBS.) 79 



British species most nearly related to the former, and have obtained 

 from my friend Mr. "William Kaye, of Hong-kong, a well-executed ori- 

 ginal drawing, by Dr. Lauder, R. N., of what I believe to be identical 

 with the latter, I may be perhaps excused if I venture to call atten- 

 tion suggestively to, and to contrast the descriptions and figures of, 

 what appear to me to be the same two forms, each respectively diffe- 

 rently designated by Bailey, Wallich, and Hobson. 



Dr. Wallich some time ago described and figured a Micrasterias, 

 under the name of M. morsa (Ralfs) var. 8 •* and if those interested in 

 the matter will compare with it the perhaps a little vague description 

 and figure given by Mr. Hobson, f I think it will be admitted that both 

 apply to and represent the same identical form. Dr. "Wallich, indeed, 

 depicts the end lobes of his plant as serrated, whilst Mr. Hobson gives 

 those of his as entire ; moreover, the latter in his description, in a puz- 

 zling and contradictory manner, calls " the surface of the frond covered 

 with small granules bordering the whole of the sinuses," so that we 

 are obliged to rely almost wholly on his figure ; but of the identity of 

 these two plants there can, I think, be no doubt. 



It is to be regretted that Dr. Wallich in his paper has spoken of the 

 Bpecies referred to as M. morsa (Ralfs), whereas the name Jf. Americana 

 (Ehr.) having the priority, it should have the precedence. It will there- 

 fore be understood, that when I here refer to 31. Americana, it is equi- 

 valent to M. morsa as alluded to by Dr. "Wallich, and I mean by the 

 former name precisely the same identical plant, — Dr. "Wallich, indeed, 

 himself draws attention to this in a note. 



This presumed form, then, of M. Americana (Ehr.), which I can do 

 nothing else than assume as identical with M. Mahabuleshwarensis (Hobs. ) , 

 Dr. "Wallich makes var. B of that species of which he considers M. Ame- 

 ricana the type, and along with it he would include both M. Baileyi 

 (Ralfs), and M. ringens (Bailey) — the two latter, indeed, forming but a 

 single variety of the assumed species M. Americana. But in this conclu- 

 sion I feel bound to say, with much deference, that I cannot at all concur. 

 Dr. Wallich, indeed, seems to overlook, and I regard the consideration as 

 very worthy of attention, that Professor Bailey, who had seen the living 

 forms, has, in his published list, J enumerated the whole three, that is, 

 M. Americana, M. Baileyi, and M. ringens, as so many distinct species. 

 I admit, indeed, that the short technical characters given by Dr. Wallich 

 would almost, if not quite as well, apply to the actual M. Americana 

 (Ehr.) ; but, paying attention rather to his subsequent general descrip- 

 tion, and to his I have no doubt very graphic figure, and comparing 

 them with Ralfs' figures, § or, even better still, with an actual specimen, 

 surely I think abundant differences will present themselves to any one 



* "Annals of Natural History," 3. S., vol. v., p. 277, PI. XIII. 10. 

 f Loc. cit, p. 168. 



% "Smithsonian Contributions to Knowledge" ("Mic. Obs. made in S. Carolina, 

 Georgia, and Florida,"), p. 29. 



§ " British Desmidiese," p. 74, t. x., 1. 



