58 ORDOVICTAN AND SILURIAN BKLLEROPHONTACEA. 



The other specimens in the same Museum are from Dudley (6/823, Salter's 

 Catalogue) and are merely internal casts. The characters therefore of the slit- 

 hand and ornamentation of the surface are ascertained from the Woolhope specimen. 



The species appears to be allied to B. sijuttmosus, Liridstr., 1 especially in the 

 matter of its ornamentation, but the mouth is less expanded, and the shell is 

 relatively broader and more globose, the dorsum also being' more broadly rounded. 

 Perner would place it in his group Sphaerocychis. 



There are many poorly preserved specimens from the Llandovery Series of the 

 Frolic, Haverfordwest, and one [28044] in Jermvn Street from Blaen-y-cwm. which 

 seem inseparable specifically from B. wenlockensis. In the shape of the shell, 

 characters of slit-band, partial carination of the distal portion of the outer whorl 

 and course of strias on the surface, they completely agree; but the striae seem less 

 regular in size and distribution than in typical AVenlock examples, and therein 

 more resemble B. squamosus, Lindstr. 



The Devonian shell from Newton referred by Phillips 2 to Jl. wenloclcensis, Sow., 

 with a query, seems to have been a very poor specimen and its specific reference 

 quite indeterminable. 



6. Bellerophon ? solvensis, Hicks. 



1873. Bellerophon solvensis, Hicks, Quart. Joum. Geol. Soc, vol. xxix, p. 50, pi. iii. tig- 33. 



Specific Characters.- — "A small species, of three very gradually increasing- 

 whorls, about one-eighth of an inch in diameter. Surface smooth, sides inflated." 



The small specimen on which Hicks founded this species is an internal 

 cast which does not admit of precise determination, and its generic position 

 in modern classification is doubtful. It should be added to Hicks' diagnosis 

 that the umbilicus is open and rather deep, exposing the 2 or 3 inner whorls; 

 and that the section of the whorls is transversely elliptical or subcircular. It may 

 belong to the group Coelocyclus of Bellerophon or to Bucania. 



Horizon. — Arenig Series. 



Locality. — Tremanhire, near Solva, and St. David's. 



Genus BUCANIOPSIS, Ulrich. 



Generic Characters. — Shell agreeing in all respects with Bellerophon except that 

 the surface is cancellated by regular revolving and transverse stria?. Whorls 

 enlarge rapidly, giving a broadly expanded aperture. Umbilicus of moderate size 



1 Liudstrom, op. cit., p. 75, pi. v, tigs. 25 — 34. 



- Phillips, 'Palaeoz. Foss.' (1841), p. 108, pi. xl, rigs. 203 a, b ; Whidborne, ' Mon. Brit. Dovod. 

 Fauna' (Palaeont. Soc), vol. i (1892), p. 329. 



