182 DR. 8. O. LINDBERG ON MESOTUS. 
is probable, however, that islands of moderate or small size, very 
distant from hny continent, have but a scanty marine flora. And 
here it may be worthy of notice that the island of Kerguelen 
(much further removed from any continent) has eight olive, nine- 
teen red, and twelve green (thirty-nine in all) of marine plants, 
and, in proportion, is therefore not richer in this respect than 
St. Helena; but of these, five are, I believe, so far as known, pe- 
culiar to that island, all the others being derivatives; and, like 
those of St. Helena, many of them have a wide distribution in 
both hemispheres; a few are South-American species. 
Remarks on Mesotus, Mitten. By S. O. Lixpbrno, M.D. 
Communicated by Dr. Bnarrgwarrs, F.L.S., dc. 
[Read March 7, 1872.] 
Iw a fine collection of mosses and lichens recently received from 
Dr. Knight, of Auckland, New Zealand, I found a large tuft of 
Sticta carpoloma, Del., which had been growing on bark; and out 
of this I picked three single stems of the very curious Mesotus 
celatus, Mitt., in Hook. f. Handb. N. Zeal. Fl. ii. p. 462 (1867), 
each of which bore one or two mature fruits. 
Though the stems from Dr. Knight are not so dense as the 
small specimen gathered by Messrs. Hector and Buchanan and 
kindly sent to me by Dr. Hooker (but bearing only a single very 
old fruit), they agree perfectly with it. But were the original 
specimens really found “on dry banks"? I think not; for, 
judging from the few stems from Dr. Knight, and from the habit 
of the plant, I conclude that it lives on the bark of trees and on 
stones, in the latter ease becoming more densely tufted, like the 
Otago specimens (H. & B.). 
As the opinions of Dr. Schimper and Mr. Mitten respecting 
its systematie position are very opposite, the former considering 
it “to be truly pleurocarpous, and allied to Esenbeckia ” (Garo- 
vaglia) the latter being disposed to place it amongst the acro- 
carpous mosses, I have endeavoured to settle the point by in- 
vestigating the structure, and beg now to offer the result of my 
observations on the specimens from Dr. Knight. 
The primary stem is creeping, about two inches long, and beset 
with dark radicles, as also are the branches, which are arcuato- 
