92 
JURASSIC, OR 
I quote Professor BlanfortPs paper, published last year; 
the plates are perhaps not yet published; as they were finished 
this year in London. He says, “ In form and sculpturing 
of the left valve it much resembles Inoc. concentricus of the 
Gault. The right valve is like an Anomia , with a narrow 
linear notch just under the hinge line.” 
Our specimen is finer than the one figured in the journal 
above quoted. It will be seen; by comparing Mr. Blau ford’s 
list with ours; how many of the Spiti fossils are identical with 
those detected by Stracliey in the Niti Pass. [See pp. 93, 94.) 
PECTEN COMATUS.-J/me. 
Plate 22; fig. 9. 
Goldfuss, Petref., t. 91, f. 4. 
This agrees almost as well with P. obscurus, Sow.; as with 
the above, and I hardly know to which to refer it. The shape 
is more like P. comatus, and the ears not so oblique as in 
Goldfuss’ figure of the other Lias species. 
P. arcuatus, Sow., of the Forest Marble of England, is 
like our shell, but is less convex, more oblique, more oval, and 
has the strise much coarser. Indeed, there are several Oolitic 
forms quite like ours. P. Lens, Sow., is rather too round a 
shell. 
PECTEN BIFR0NS.-.V. Sp. 
Plate 22, figs. 5—7. 
Half an inch long, and rather less broad : ovate, excluding 
the broad ears, which are four lines broad. The posterior ear 
is sunk, and has strong ridges of growth, but very faint radi¬ 
ating lines. The shell is gently convex. 
The ribbing is peculiar, and wholly different on the internal 
and exterior aspect of the shell. Within (fig. 5 c) there are 
about nine strong ribs most prominent at the margin. Out¬ 
side, the more convex valve has at least twice as many, each 
