FOSSILS OF THE CARBONIFEROUS LIMESTONES. 



311 



Nautilus Avonensis, n. sp. (Fig. 124), coll. J. W. D., Windsor, 

 Minudie. — A large species, the outer chamber sometimes two inches 

 or more in diameter. AVhorls much flattened dorso-ventrally, slightly 

 angulated at inner edge. Siphuucle dorsal, septa convex, about one- 

 eighth of an inch apart. Belongs to genus Cryptoceras, D'Orbigny. 

 Abundant at Windsor, and named after the Avon River, on the banks 

 of which it occurs. 



Gyroceras Harttii^ n. sp. (Fig. 125). A fragment of a small angulated 

 species, resembling N. sulcalus^ Sowerby, coll. J. W. D., Windsor. — It 

 has the whorls somewhat quadrate, with two broad flutings at the 

 sides, and two narrower flutings at the edges of the flat dorsal surface. 

 The inner surfiicc is regularly rounded, and the siphuncle is dorsal. 



Fig. 125.— Cryroceras Harttii. 



Orthoceras laterale, Phil., collected by Professor How at Kennet- 

 cook. — Resembles this species, as figured by De Koninck, too closely 

 to permit me to distinguish it. 



Orthoceras dolatum^ n. sp. (Fig. 12G), coll. J. W. D., W^indsor. — 

 Like 0. pi/gmaeum, De Koninck, in external form. Siphuncle mar- 

 ginal, slightly beaded ; shell flattened at one side. Septa one-half 



the larger diameter distant from each other. 



Fig, 126.— Orthoceras 

 dolatum. 



Fig. 127. — Orthoceras 

 Vimhhonense. 



Fig. 12%.— Orthoceras 

 laqueatum. 



e^ 



Orthoceras Vindohonense, n. sp. (Fig. 127), coll. J. W. D., Windsor. 

 — Section nearly round. Siphuncle about one-third the diameter 



