208 
AMMONITES triplicatus. 
TAB. XCII.—Fig. 2. 
Srec. Cuar. Involute, inner whorls exposed ; radii 
twice curved, alternately one long and three 
short; a smooth line along the front; aperture 
obovate. 
a 
I cout only describe a cast of this, the shorter radii 
extend rather more than half-way from the front towards 
the centre, there are commonly three, but sometimes only 
two between a pair of long ones; the long ones are rarely 
forked. Volutions about four. Aperture about half the 
diameter long, and one-third wide; septa rather distant. 
This came from Portland Island, it is a cast in pyrites 
with Carbonate of Lime in the chambers. I was fayored 
with it by the late Mr. Bryer of Weymouth. 
AMMONITES binus. 
TAB. XCIL—Fig. 3. 
Spec. Cuar. Involute, depressed, keeled; inner 
turns two-thirds exposed; radii diverging in 
pairs from rourd tubercles, swelling and then 
turned up towards the front and disappearing ; 
keel small, entire; aperture oblong rectangular, 
angles rounded. 
a 
Voxurions about four; aperture one-third the diameter 
long, and rather more than one-sixth wide; there are some- 
