84 
JURASSIC; OR 
twelve or fourteen in number; near the umbilicus, and bifurcate 
at another series about lialf-way across the whorl, equal in 
number to those along the umbilicus. A few non-tuberculate 
and simple ribs intervene, and all terminate on each side of 
the siphuncle in a row of compressed tubercles. The superior 
lateral lobe is longer than the ventral;—broad, and termin¬ 
ating in three branches, of which the central is the longest. 
The species bears much resemblance to A. octagonus , Strachey, 
but has not the catenate ribs of that species, while the 
ventral tubercles are much more numerous. 
AMMONITES MEDEA— Strachey, MSS. 
Plate 19, fig. 5 a. 
The only specimen of this MSS. species of Colonel Strachey 
in his collection is the fragment figured, from which it is 
difficult to pronounce upon its affinities. It may be either, as 
surmised by Colonel Strachey, a species allied to A. Jason, 
Zieten, or a portion of a large specimen of the tuberculate 
form of A. WallicZiii, Gray. 
AMMONITES WALLICHII.-<?my. 
Plate 15, figs. 1 a-c; Plate 19, figs. 1 a-c, 2 a-c. 
Ammonites WallicMi, Gray, Hardwicke’s Illustr., vol. i, plate 100, fig 3. 
„ „ Blanford, Journ. As. Soc. Beng., 1863. 
A. testa discoidca, compi'essa, flexuoso-costata. An.fr. pi us minusvc 
planatis, medio ventre excavatis. Costis angustis plcrumque bifurcatis 
apud ventrem interrnptis, nonnunquam tuberculatis (senioribus 
nonnullis continuis). L mbilico lato. Apertura ovata anticc truncuta. 
Lobis latcralibus septorum 4. 
Diameter ... 
Ditto of outer whorl 
... ... * 3'75 in. 
1-35 „ 
- 
Thickness 
. 1-20 „ 
Spiral ratio 
Immersion of whorls 
Thickness: diam etcr 
... 2: 1 to 5:2 
.. i i 
** 7 (T 
7 3 
•" 8 » 4 
* A specimen in the British Museum measures not less than six inches in 
diameter. 
