386 CARBONIFEROUS FOSSILS. 



nized, should any collectors visit in future its rugged habitat. 

 Fenestella Martis, of Fischer (Oryct. Gouv. Moscou, pi. xxxix., 

 fig. 2), is not unlike it, but the apertures are oval and but little 

 broader than the interstices or branches, which are decidedly 

 thicker than in ours. The same may be said of the F. cribri- 

 oculata, Verneuil, figured in Count Keyserling's ' Reise in Pet- 

 schora-land/ pi. iii., fig. 7, which has neither so flat a surface 

 nor such large perforations. 

 LOCALITY. Depot Point. 



SPIRIFEE KEILHAVII (VonBuch). 

 Plate XXXVI., fig. 9, 10, 11. 



S. Keilhavii, Von Bucli, Trans. Roy. Acad. Philos. Berlin, 1846, p. 65, 



fig. 2 in the plate. 

 SYN. -S. Sarance, De Vern., in Keyserling Reise in Petschora, pi. viii., 



figs. 4, 5. 



There can be no doubt of the identity of this shell with that 

 so carefully described by VonBuch from the "Producten- Sand- 

 stein" of Bear Island. The square form, short hinge line,* 

 elevated beaks, and broad deep plaits with ribs upon them, all 

 agree exactly ; and we think that the variety we have figured 

 (fig. 11) will agree equally well with Count Keyserling's 

 figures of the S. Saranae from Petschora. It is so distinct a 

 species from any European ones as not to need comparison, 

 and Yon Buch has compared it with its allies from New Hol- 

 land and South Africa. 



Our specimens are all of the larger ventral valve. In the 

 ordinary variety (figs. 9 and 10) they are an inch and a half 

 long, and as much broad, with the hinge-line, in full-grown 

 shells, shorter than the entire width. Beak very convex, ele- 

 vated and incurved, furrowed to the apex, from which radiate 



* Von Buch says, " It belongs to the division in which the hinge 

 line is as long as the shell." This must be intended to mark its re- 

 lations with broader-winged Spirifers rather than with the smooth 

 rounded forms, for one of its best characters resides in the very short 

 hinge-line. 



