18 MOLLUSCA FROM THE GREAT OOLITE. 
fold or varix, of which there are two upon the last volution. The inner lip is broad and 
distinct, the channel is short and straight. A small canal passes from the aperture to the 
apex of the rudimentary digitation. 
M. Deslongchamps has described this species from three small specimens, which are 
very imperfect, having only the last volution. The name is scarcely appropriate to full- 
grown individuals which nearly lose the hook-lke digitation: m one instance only have 
we noticed the Aamulus of the dimensions figured by M. Deslongchamps, and this occurred 
in the smallest of our specimens, which was but little larger than the Norman one. It 
would, therefore, seem that this feature was of an uncertain character, and disappeared at a 
later period of growth. 
Locality. he beds of planking at Minchinhampton Common, and their equivalents, 
the white stone of Bussage and Eastcombs, have supplied all the specimens which have 
come to our knowledge. It is not very rare. In the Great Oolite (pierre blanche), 
Langrune, Normandy. (Des/.) 
Avaria Puiuuipsi, D’ Orb. sp. Plate IIT, figs. 5, 5a. 
Prerocera Puitiipsit, D’Orb. 1850. Prod. Paléont, p. 270. 
RostELLARIA composita, PAil. 1835. Geol. Yorksh., i, t. 9, fig 28, (not Sow.) 
A. Testa turritad ; spird elongata; anfractibus numerosis, convexis, vel subangulatis, 
transverse striatis, et costis obliquis numerosis approximatis ; anfractu ultimo bicarinato ; 
ald unidigito, cauda recta, breviusculd. 
Shell turrited; spire elongated; whorls numerous, convex, or subangulated, trans- 
versely striated, and ornamented with numerous closely-arranged oblique ribs upon the 
lower half of each whorl; the last whorl is striated and bicarmated, terminating in a simple 
or undivided wing ; the caudal extremity is straight, smooth, and of moderate length. 
A. hamus is the species which approximates most nearly to it; but in that shell the 
longitudinal costa are less numerous, not oblique, and are visible throughout the length of 
the whorl; whereas in the 4. Phillipsii they occupy the lower half only, and form an angle 
at their upper termination. The upper and larger carina upon the last whorl is more 
smooth and less prominent than in the 4. Aamus, and the entire form of the shell more 
lengthened or slender. 
Locality. Scarborough, in dark chocolate-coloured argillaceous shale. Great Oolite, 
(Phillips.) 
AuariA pacopa. Plate ITI, fig. 6. 
Testa turritd ; anfractibus numerosis, in medio carinato-crenatis, ultimo bicarinato ; 
carinis tuberculatis ; anfractibus transverse striatis ; striis duabus prominentibus suturam 
