ARCHER, ON MICRASTERIAS MAHABULESHWARENSIS. 261 
I now turn to the other form described by Hobson—his 
Docidium Pristide. In the month of June last I received 
from my friend Mr. Kaye, at present resident at Hong- 
Kong, amongst others, a drawing (Plate VII, fig. 1) from 
the pencil of Dr. Lauder, of a form of which I was at once 
quite disposed to regard as Triploceras gracile (Bailey).* I 
was somewhat surprised a few days after, on the ‘ Quart. Jour. 
Mie. Sci.’ for July, 1863, making its appearance, to find 
what I am equally disposed to regard as the same plant 
described and figured} as a new species; but in regard to 
this, of course, not having seen the actual specimens, I can 
venture only to offer an opinion. Mr. Hobson says his plant 
can hardly be the Docidium (Triploceras) verticillatum (Bailey), 
inasmuch as in the former the teeth are sharp, not obtuse, as 
in the latter; and in this I would agree with him, as D. (Tri- 
ploceras) verticillatum has been more lately restricted by 
Bailey, in which species the teeth or projections are emargi- 
nate. But I think ifreference be made to Ralfs,t Mr. Hobson 
will find the projections equally sharp at their summits as in 
his own figure ; and Bailey’s figure, clumsy as it is, seems to 
show the character of the ends more lke Mr. Hobson’s 
drawing. Mr. Hobson seems to be unaware that Professor 
variety of M. morsa (properly MW. Americana). Grunow’s plant seems to 
me well distinguished from Wallich’s—that is, from 1. Mahabuleshwarensis 
—the description and figure, by Hobson, of which latter Grunow had not 
seen—first, by the basal inflation of the segments; and secondly, by the 
deeply trifid lateral lobes of the former; and thirdly, as it seems to me, by 
the end lobe, apparently from the figure diverging into four equally radiating 
processes, none of which stand vertically to the plane of the frond. Grunow, 
it is true, is disposed to think that the plant figured by Wallich as (what 
I venture to call the assumed) “var. y” of Micrasterias expansa (Bailey), 
tlhe (assumed) “var. 6” of MZ. morsa (properly WM. Americana), and his own 
M. Wailichii, may all three be but varieties of one species. Grunow even 
supposes that Wallich may have overlooked in his “ var. 6” of M. Ameri- 
cana the basal inflations which appertain to WZ. Wallichii ; but Dr. Wallich 
is undoubtedly too excellent and accurate an artist to omit so conspicuous 
a character. But Dr. Wallich makes his “var. y” of M/. expansa at least 
specifically distinct from “var. 6” of M. Americana; however, as above 
stated, I should think there is a greater affinity between these two forms 
than between J/. Americana, “var. 5” (i.e. M. Mahabuleshwarensis) and 
M. Americana (¥hr.) proper. All three I should venture to hold as quite 
distinct, and I think L am justified in retaining this view until the non- 
reconcileable intermediate forms turn up. Why, I would with all deference 
ask, so much assumption, when the plants are there, quite distinct, to speak 
for themselves ? 
* Brit. Des.,’ t. xxxv, 9 c.; also ‘Smithsonian Contributions to Know- 
ledge,’ Bailey, ‘‘ Mic. Obs. in 8. Carolina, Georgia, and Florida,” p. 38, 
Pra, te. 10. 
+ ‘Quart. Journ. Mic. Sci.,’? N.5., Vol. IIT, p. 169. 
t Op. cit, Pt. xxxv, fig: 9, ¢, 
