328 FISSURELLID®, 
In 20 to 100 fathoms water. Fossil, in the glacial formations of 
North Britain. &. Noachina, Linn. (1xxxiv, 33). 
cRANopsIs, Adams. Fissure about the middle of the anterior 
side; an internal vaulted chamber over the foramen, resembling 
that of Puncturella, Cr. pelex, Adams (Ixxxiv, 34, 35), from 
the China seas, is the type, and one or two additional species 
have been since described. 
SEMPERIA, Crosse. (Named after M. O. Semper, of Altona.) 
Shell conical, apex posteriorly recurved, anteriorly fissured ; the 
fissure is marginal in the young shell, but in the adult the margins 
grow around it so that it becomes subdorsal, or separated from 
the margin externally, though connected with it internally by a 
channel. HKmbraces at different growth-stages characters of 
Rimula, Emarginula, Clypidina. 2 sp. Madeira. Fossil; Paris 
basin. SS. elegans, Crosse (1xxxiv, 36). 
EMARGINULA, Lam. 
Etym.—Diminutive of emarginata, notched. 
Syn.—Nesta, H. Adams. 
Distr.—40 sp. West Indies, Britain, Norway, Philippines, 
Australia. Range from low-water to 90 fathoms. Fossil, 40 sp. 
Carboniferous—. 4. fissura (1xxxiv, 37). 
Shell oval, conical, elevated, with the apex recurved; surface 
cancellated ; anterior margin notched. Muscular impression 
with recurved points. | 'The nucleus (or shell of the fry) is spiral, 
and resembles Scissurella. The anterior slit is very variable in 
extent. The animalof Emarginula (and also of Puncturella) has 
an isolated cirrus on the back of the foot, perhaps representing 
the operculigerous lobe.—Forsers. Lingual dentition (xii, 50), 
median teeth subquadrate; laterals four, oblong, imbricated ; 
uncini about 60, the first large and thick, with a lobed hook, the 
rest linear, with serrulated hooks.—LoveéEn. 
SUBEMARGINULA, Blainv. (Hemitoma, Swain. Siphonella, Issel. 
Montfortia, Recluz.) Anterior margin with a slight channel and 
a canal-like prolongation of it proceeding towards the apex, on 
the inside face of the shell. . octoradiata, Sowb. (1xxxiv, 37). 
zEIDORA, Adams. Shell like Emarginula, with the margin of 
the aperture crenulated and anteriorly deeply fissured, but there 
is posteriorly an internal, flat, semilunar septum present, which 
distinguishes this subgenus from any other Fissurellide. £. 
reticulata, A. Ad. (Ixxxiv, 39, 40°. 
DESLONGCHAMPSIA, M’Coy, 1850. . (Dedicated to Dr. Eudes 
Deslongchamps, the renowned French paleontologist.). Shell 
(Ixxxiv, 41). *¢ : a yar Dy nif asibs 
