3(5 FAUNA OF THE CORNBRASH. 



Distribution. — This species is most abundant at Bedford (Midland Railway Pit), 

 Rusliden, Tlirapston, Thorn, S. Cerny, Roade (fragments), and Scarborough. It 

 was also recorded by Professor Buck man from Fairford. 



Nautilus calloviensis, Oppel. Plate IX, fig. ] 3. 



1842. Nautilus hexagonus D'Orbigny (uon Sowerby), Terr. Jurassique, p. 161, pi. xxxv, figs. 1, 2. 

 1856. — calloviensis Oppel, Jura formation, p. 547. 



Type. — This must be taken from D'Orbigny, as Oppel refers especially to the 

 species of that author, saying at the same time that Sowerby's species differs from 

 it by having a wider mouth-opening. D'Orbigny says: " Shell slightly compressed, 

 smooth, or with fine growth-lines, umbilicus very narrow. Whorls angular, back 

 flattened, sides flattened, with a third less marked round the umbilicus, greatest 

 transverse diameter near the umbilicus. Mouth depressed, broader than high, 

 angular. Sutures simple, deeply furrowed in the middle, rising at the edge of 

 the umbilicus, and furrowed again towards the middle of the back." From the 

 lowest Oxfordian. 



Description. — The specimen referred to this species is remarkable for the 

 change it undergoes. If we take only the portion of 64 mm. diameter, as 

 figured by D'Orbigny, it agrees admirably with the above description ; but parting 

 from that size the swelling at the side enlarges, and the onward growth becomes 

 more rapid, while the periphery becomes more markedly angular. It then looks 

 very like A. truncal us. There is almost an idea that it is approaching N. giganteus. 

 It seems probable that N. calloviensis may represent the young of N. truncatus, 

 and this specimen shows better than any other the change of character. On this 

 ground we might include this with the latter species. 



Distribution. — This specimen was obtained from Peterborough by Prof. 

 Garwood, and is now in the Sedgwick Museum. 



Order AMMONOIDEA. 



All the records of Cornbrash Ammonites, except one, have been made under 



that name as generic. They are as follows : 



*A. bdkerias (36). A. herveti (1, 5, 6, 27, 28, 30, 44, 45, 



A. brocchii (23). 46). 



*A. bnllatus. A. hochstettehi (21, 23). 



*A. discus (1, 2, 3, 4, 7, 15, 26, 27, 33, A. huinphriesianm (23). 

 34, 36, 41, 46). A. jurensis (23). 



