EUPHEMUS. 71 



Bemarhs. — Phillips figures two specimens, and adds tlie following particulars : — 

 aperture very expanded ; no umbilicus, no band ; ridges crenulated ; furrows 

 crossed by fine lines of growth, retroflexed from the mouth. Interior of the shell 

 quite smooth. 



There is certainly no keel, but there is a slight sign of a sinus-band between 

 the two central ridges, shown by a faint indication of recurved growth-lines in it. 

 The lateral lines of growth retroflexed from the mouth are also just visible. There 

 are no signs whatever in our specimen of the crenulations on the spiral ridges 

 which are described by Phillips. It seems, however, possible that Phillips's 

 enlarged pattern (' Pal. Foss.,' fig. 199 d) may have been taken from this specimen 

 as well as his other figure, and if so the signs of crenulation in it are deceptive, 

 being due to a slight fracture of the summits of the ridges. 



Affinities. — It is difiicult to define the species from the small portion visible in 

 our only specimen. From the true Eu. TJrii^ as restricted by de Koninck,^ it is 

 distinguished by the absence of an elevated keel. Eu. Orhignii, de Koninck,^ has- 

 coarser and closer spiral ridges. Eit. Horioni, de Koninck,* has more numerous 

 striae. Eu. invitabilis, de Koninck,^ has more unevenly arranged ridges, and is a 

 flatter shell. Eu. filosus, de Koninck,^ seems to approach nearest to it, but differs 

 in the same particulars. As, however, our specimen only shows the inner whorl, 

 it is hard to say whether these distinctions would remain true if a perfect 

 specimen of it could be compared. At the same time it seems most probable that 

 they would, and that they are sufficient to give this form a claim to a distinct name ; 

 especially considering that, as it belongs to a different formation from the above- 

 mentioned shells, the presumption is that they are distinct. Moreover, though 

 Romer's figure of his Devonian shell is very poor, it shows that, if it represents 

 the present species, its shape is very difi'erent from that of any of the Belgian 

 forms. 



D'Orbigny figured the young shell of Oxygyrus Kevaiidreni, Rang,'' of which he 

 remarked that it is so like in shape and ribbing that it would be hard to 

 distinguish it if it came from beds of the same age, and which he considered to be 

 evidence of the relationship of Bellerophon to the Atlantidse.^ 



1 1828, Fleming, ' Hist. Brit. Auim.,' p. 338. 



2 1883, de Koninck, ' Ann. Mus. Eoy. Hist. Nat. Belg.,' vol. viii, p. 157, pi. xlii, figs. 40—43. 



3 Ibid., p. 156, pi. xlii, figs. 5 — 7 ; and pi. xliii, figs. 9 — 13. 



4 Ibid., p. 159, pi. xliii, figs. 18—21. 



5 Ibid., p. 159, pi. xliii, figs. 22—25. 



6 Ibid., p. 160, pi. xliii, figs. 14—17, 26—34. 



7 1840, de Perussac and d'Orbigny, 'Hist. Nat. Ceph.,' p. 198 (Bellerophon), pi. vi, figs. 1, 2. 



8 1887, Fischer, ' Manuel Conchyl.,' p. 582, fig. 347. 



