416 PYRAMIDELLIDA. 
scription of the same object: this remark is applicable to all 
the Chemnitzie. The tentacula are short, flattened, triangular, 
not pointed, and bevelled like an awl, setaceous, and in some 
animals suffused with sulphur-yellow; each has also a longi- 
tudinal line running between the bevels; the eyes are at the 
internal points of the basally-coalescing tentacula, immersed 
in the skin. The operculigerous lobe is inconspicuous, almost 
obsolete, with scarcely a trace of lateral extensions. 
In this species the minute branchial plume was found in 
the usual position, attached to the neck and mantle ; no head- 
lappets, with scarcely the rudiments of a veil; the anal pellets 
were observed to be ejected from the right side; the male 
organe générateur was not seen. This species scarcely differs 
from C. acuta: the variation is in colour, and in the anterior 
part of the foot being less hollowed out. 
There are five or six varieties slightly differmg im con- 
tour. Their principal habitat is at the back of the auricles 
of the Pecten opercularis of the coralline zone, where they 
may be seen in clusters of six to ten, imbedded in animal 
mucus. 
This is a very common species, and is, I think, undoubtedly 
Montagu’s shell. I draw my conclusions from his figure and 
notes, in the ‘Testacea Britannica,—not from the fragment 
of what is said to be his type, that still exists, and is enveloped 
in dubiety, whether it be genuine, spurious, or a substitution 
by accident. When I stated in the December ‘ Annals’ for 
1850, in the memoir on the Pyramidellide, under the article 
Chemniizia eulimoides, that that species, the very common 
C. pallida of authors, was not the “pallida” of Montagu, I 
did so, from having been led to believe that an undoubted 
type of his species existed to prove that fact; the ‘ British 
Mollusca’ has since informed me that that is not the case; 
I therefore gladly revert to the commonly received opinion, 
which I had previously entertained, that the well-known Chem. 
pallida of almost all authors, or one of its imumerable varie- 
ties, is the true Montaguan “pallida.” Montagu has stated 
his “pallida” to be very rare. When he wrote, the minuter 
species were procured by ocular labour from the littoral sands, 
