Dr. Smith's Remarks on the Generic Characters of Mosses. 255 
Mnium, that it bears two different kinds of heads, or fructifica- 
tion ; the one powdery and naked, that is, destitute of calyx and 
capsule; the other of the same capsular nature as in Bri/um and 
Hypnum, those great genera which, in the work of Dillenius, 
swallow up almost all the rest of this natural order. He considers 
this character as abundantly sufficient to*distinguish Mnittfn from 
all other mosses, and proceeds to inquire into the nature of these 
different parts of fructification. He presumes the capsules to be. 
as he believed of other mosses, anthem, and the powdery heads 
to produce seeds, or at least what is analogous to them. AVe now 
know that he mistook the male # for the female, and vice versa', 
though his having called the supposed antherce by the name of 
capsules, has concealed his mistake from common observation, 
and thrown all the glare of his error on Linnaeus, who adopting 
his hypothesis, at the same time corrected, as he thought, his 
phraseology. We now resume the language though we discard 
the ideas of Dillenius, calling his and Linnaeus's supposed antherce 
by their proper name of capsulce. Nor, while we profit of the 
brilliant physiological and botanical discoveries of Micheli and 
Hedwig, do we find any reason to follow the former in his care- 
less denomination of the part in question, which he calls capitu- 
lum, nor to adopt the new word invented by the latter, without 
any reason or advantage, sporangium. 
Dillenius describes eight supposed species of Mnium; for he has 
referred to this genus every thing in which he found a powdery 
head, even though he did not meet with the capsule. This has 
led him into a great error. In his first, second, third, fourth and 
eighth species he is indeed, as far as any one could at that time 
be, correct; but his remaining species are not even mosses at all. 
The fifth and sixth are Jmigermannice, a mistake which Linnaeus 
did not correct; and the seventh is, as the careful Micheli had 
already 
