120 ARCHER, ON PALMOGL@A MACROCOCCA. 
of homomorphism, even in organisms very high in the scale, 
and well know that such sometimes do not indicate even any 
affinity, not to speak of identity. And I should certainly be 
disposed to imagine that homomorphs are not less likely to 
occur in such simple plants as those under consideration 
than in regard to the more complicated and elaborate organs 
of higher existences, even in animal life. Dr. Hicks * speaks 
of “large oval cells precisely similar to Palmogloea” (Kiitz.) 
(Cylindrocystis, Menegh., Coccochloris, Hass.), as occurring 
during the development of certain lichen-gonidia, and he 
considers the oval cells represented in his figure + as “ visu- 
ally identical”? with “ Palmoglea Brébissoni.’ If he means 
by this Palmoglea Brébissonit (Kiitz.), which Kitzing makes 
out to be identical with Palmella cylindrospora (Bréb.), which 
latter Ralfs considers identical with his Penium Brébissonii, 
then I am bound to say I cannot agree that Dr. Hicks’ form 
is by any means “ visually identical” with that mdicated by 
the names just quoted. That alluded to (Peniwm Brébis- 
sonii, Ralfs) is undoubtedly a Cylindrocystis, and Hicks’ 
figure suggeststo one more the idea of a Mesotzenium, with the 
broad side of the clorophyll-plate uppermost, but does not at 
all call to mind a species of the former genus. If it be 
assumed as presenting a form of Mesoteenium, the granular 
endochrome, which so. often obscures the view of the chloro- 
phyll-plate, seems to be very deficient, for the central cor- 
puscle is to be seen in all the cells figured. ‘This central 
corpuscle is regarded by Hicks as a nucleus; it would seem 
far more probably to be merely a starch-granule, or a “ chlo- 
rophyll-vesicle” (Nag.). In Cylindrocystis Brébissonii two 
such granules occur in ordinary cells, and four in cells about 
to divide, and they appear quite homologous and identical in 
nature with the similar bodies occurring in Closterium, &c. 
&e. If by Palmoglea Brébissonii is meant by Hicks Cocco- 
chloris Brébissonii (Thwaites),{ although Thwaites’ descrip- 
tion and figures hardly admit of a certain conclusion as to 
whether any species more recently described by Continental 
writers may be identical with it, yet Hicks’ figures do not at 
all seem to me to be identical with, or even at all to resem- 
ble, those of Thwaites. The former represent a rather 
narrow, egg-shaped form, while the latter is described as 
“‘cellulis subspheericis vel rotundato-ellipticis ;” and, setting 
aside the scantiness of the accompanying filaments (which, as 
1 before indicated, I conceive have no connection with the 
* Tioe. ett., p. 17: 
+ Ib., pl. a, figs. 11, 19. 
x ‘Annals of Natural History,’ n. s., vol. iii, p. 243. 
