FIFTH, OB \', iSSK EB \N BB \\< 11 197 



mens of this species in the Stutl I Museum, Upper Bucklandi 

 • > 1 1 1 Balingen, showed living chambers, as pointed out to me by Prol 



null shorter than in p ind the sutures distinct The 



peculiar folds ■ppearing on -nine shells, and the form and aspect <>i the whorls, 

 like those <>l tli<- nealogii s show that their affinities are in 



the direction of this QuenBtedt's 



ptions from Pforen fully sustained the above, and a fine Buite of the same 

 ir, in the corresponding horizon, exhibited several forms transi- 

 tional to the yo 



M -ili. in the Museum « * t ' the Polythenic al Zurich, Bhowed me 



ii specimens ol in which the keel was bo fainl is to be hardly per- 



de, and the Btriations n<> better marked than in Psiloteras, These were 



. and were found at Salins associated with typical siriariet. The 



aperture- are also similar to tli"-'- "! /'■■ pi 



Agassiccras Scipionianum, n 



Plata \ ii. i , t . i i i Plata 1 i •- I1-1S loma, n. \m i 



Amm. 



Amm - - t pi XVli ) 



\\i;i..iii. Liai \ in n»- . p 280 pi. xiii ti_-. 1 •'.: pi i 

 \rion in Luxemburg, Gmiind. 



Th eedingly. S the young show a crenulated keel, 



ami they may also be either Bmooth or pilated <»n the Bides, The abdomens are 



i. ami -a-innallv. though very slightly, channelled. The form of the 



whorl in tl 'her very gibbous, Plate VII. Fig. 11. 12, or com* 



i. The pike also varj from comparatively thin and dep 



••nineiit and well defined, with <>r withoul tubercles; they may also be very 



nuine. w in number, and be very distinct, >>r thick, awkward-looking 



immonly supposed that the true affinities ■ >! this fossil were 



with f ; ip, hut it- development is altogether peculiar, and its 



sutures are distinctly arietian. There are two varieties of this Bpecies with dis- 



tinet : bill similar adults; one, a- described abovi !iImiiis 



nml heavily pilated, 1 and another mure compressed at all stages, and approxi- 

 matii I itt< i may be identical with I 



or it ma\ be distinct ; the material- at hand are not Bufficienl t" determine tins 



In ppresaed, the sides I ome Matter and more 



liculaa bend leas abruptly and curve slightlj forward, the 

 channels d but the keel remains verj prominent and sharp Th< 



ju-t before the pits lull of 



ll the -hell |- not -ii in\ nlllte 



i, nt the) become i 



