ANIMALS. 177 
from each umbone to the pallial line, at the same time curving slightly towards the 
posterior end. (Vide Pl. XV, fig. 22.) 
Leda Vinti, which is a rare species, occurs in the lowest beds of Whitley and 
Humbleton Quarries, and in both the compact and crystallized rocks near Byers’s 
Quarry. According to Geinitz, M. Mielecki has discovered it in the Zechstein-dolomite 
of Katzenstein, in the Hartz. 
Family SoLEMY1D#, Philippi. 
“The very singular So/enomye ought to constitute a family of themselves, the gills 
not being lamellate, but twice pectinate or pimunate: the mantle is closed, attached 
to the whole of the shell, not reflexed at the ventral margin: siphons none, the 
aperture for the anal excretions, and for the branchial water being undivided. 
Epidermis shining, reaching beyond the margin, and elegantly slashed; not of a 
horny substance, for, when treated with caustic potash, it does not exhale ammonia, 
but seems rather of a glutinous nature.’ (Philippi.) 
This very singular family has now existed during an immense lapse of time on our 
planet. Professor Phillips, by his discovery of the so-called Solemya primeva, was the 
first to make known its having lived during the Carboniferous epoch. I have else- 
where noticed my discovery of species belonging to the Devonian rocks of the Kifel, 
and to the Magnesian-limestone formation of Durham.’ I am not acquainted with any 
secondary or tertiary forms; but their having existed during the primary period, and 
their being now wide-spread denizens of our seas, are, in my estimation, positive 
proofs of the family having lived during the mtermediate periods. The recent Solemya 
and the palzozoic /aneva are the only genera known belonging to the group. 
Genus Janeia, King. Ve 
Diagnosis—Oblong : inequilateral, the posterior side being the longest. Cartilage 
internal; attached to a considerable portion of, and a little within, the dorsal margin 
of the valves; dilated, and somewhat oval within the umbonal cavity; narrow, and 
elongated behind it.’ 
Type, Solemya primeva, Phillips. 
1 Enumeratio Molluscorum Sicilie, p. 15. 
2 London Geological Journal, vol. i, p. 10. 
3 For further remarks on this genus, see APPENDIX. 
