BY R. ETHERIDGE, JUNR., AND JOHN MITCHELL. 503 
The previous use of Dalmania seems to have escaped the 
notice of Barrande, for we find him using the name throughout 
the first volume of his magnificent work on the Bohemian Silu- 
rian System, until nearly the close of the volume, when for a 
single species in the Addenda, the word Dalmanites is employed, 
and continues throughout the atlas. It is therefore possible that 
in the interval Barrande discovered the inutility of the name 
Dahnania, and by the use of the termination ites sought to dis- 
criminate between Dalmania, Emmrich, and Dalmanites, Barrande. 
At the same time an objection has been raised by some authors 
that even Dalmanites is not sufficiently distinctive. 
Prof. James Hall, in one of his numerous critical contributions 
to American Paleontology, seems inclined to advocate the claims 
of Odontocephalus, Conrad, 1840 (= Oryphceus, Green, 1837, non 
Cryphmns, Klug, 1833, a genus of Coleoptera; and Pleur •acanthus, 
M. Edw., 1840, non Pleur acanthus, Ag., 1837, an Ichthyodorulite). 
If, however, Odontocephalus is restricted to forms resembling its 
type species, Asaphus selenurus, Eaton ( = Calymene odontocephala, 
Green), in which the anterior border of the cephalon is denticu- 
lated or fimbriated, a good generic distinction, it cannot possibly 
clash with Dalmanites. Indeed, we imagine this had already 
struck Prof. Hall, for in the seventh Vol. of the Paleontology of 
New York, by himself and Mr. J. M. Clarke, we find both names 
acknowledged much on the lines now explained. Pleur acanthus 
might have been adopted had not Agassiz in 1837 made use of 
the term for an Ichthyodorulite. 
Unless we have overlooked any step in the discrimination of 
this generic type, and that is not impossible, there remain two 
courses open to us— either to adopt Dalmanites, following Bar- 
rande, or to propose a new genus. We are loth to adopt the 
latter alternative, more especially as Hall and Clarke have pro- 
posed as a subgenus under Dalmanites the name Hausmannia, 
with practically the same characters as the genus proper. They 
remark, "It is here proposed to group under the type Hausmannia 
the typical and unvaried forms of Dalmanites, which follow the 
