212 A. Smith Woodivard — Oreensand Ganoid Fishes. 



of Kursk, Eussia, probably of this species, is ascribed to " Sauro- 

 cephaltis striatus, Ag." by Y. Kiprijanoff, Bull. Soc. Imp. Nat. Moscou, 

 vol. xxxiii, pt. i (1860), p. 666, pi. x, fig. 3. 



3. ProtospJiT/rcena Keepiiigi, sp. nov. Woodcut, Fig. 4. 



Type. Imperfect rostrum : Wood wardian Museum, Cambridge. 



Eostrum remarkably stout and short, circular in transverse section, 

 only slightly flattened on the top at its base (Fig. 4a) ; external 

 surface ornamented with reticulating rugae. 



This species is known only by the unique type specimen obtained 

 by Mr. Henry Keeping. 



4. Protosphyrcsna ornata, sp. nov. PI. VIII, Fig. 7. 

 Type. Imperfect rostrum : Woodwardian Museum, Cambridge. 



Eostrum much elongated and attaining a length of about 0-2 m., 

 with a transverse diameter probably of 002 m. or 0-025 m. at its 

 base where the vomerine teeth are implanted ; vomerine area 

 elongated, and the rostrum much laterally compressed, except 

 towards its attenuated distal extremity, which is round in section ; 

 the rounded upper contour of the rostrum gradually becoming raised 

 into an obtuse median longitudinal ridge at its base and ornamented 

 with coarse rugse, which frequently subdivide into tubercles and are 

 mainly longitudinal in direction though partly turned obliquely 

 downwards ; the lateral portions ornamented with much finer 

 longitudinal rugse, which tend in part to converge at the middle of 

 the side and form a slight median longitudinal ridge on the inferior 

 aspect for some distance in advance of the vomerine area. 



This appears to be the commonest species of ProtospJiyrcena in the 

 Cambridge Greensand, and the rostrum is readily distinguished both 

 by its lateral compression and the unique ornamentation. The type 

 specimen, shown of the natural size from the left lateral aspect in 

 PI. Vni, Fig. 7, is the finest example hitherto discovered. 



5. Protosphyrcsna depressa, sp. nov. PI. VIII, Fig. 8. 



Type. Eostrum : Woodwardian Museum, Cambridge. 



Eostrum comparatively short and depressed, its length apparently 

 not exceeding 0-055 m. in a specimen measuring 0-025 m. in 

 transverse diameter where the vomerine teeth are implanted ; upper 

 aspect flattened, almost hollowed, and the sides converging below 

 so that the transverse section (Fig. 8a) appears triangular with 

 rounded angles ; surface smooth or in part slightly rugose. 



6. Protosphyrcena brevirostris, sp. nov. PI. VIII, Figs. 9, 9a. 

 Type. Base of rostrum: British Museum (Jesson Collection). 



Eostrum comparatively short and acute, its length apparently not 

 exceeding 0-05 m. in a specimen measuring 0-025 ra. in transverse 

 diameter whei-e the vomerine teeth are implanted ; upper aspect 

 and sides flattened, the latter converging below in a median inferior 



