170 FISSURELLA. 



F. glaucopsis Rve. Conch. Icon. f. 28, Aug., 1849. — Sowb. Thes. 

 p. 188, f. 45. 



Allied to alabastrites in color, to vema in form and character of 

 the fissure. It may prove to be a variety of the vema. 



F. conioides Reeve. PI. 38, fig. 79. 



Shell ovate, elevately conical, thick, radiately corrugately ribbed, 

 ribs very irregular and rugose ; orifice ovate, central, white, ashy- 

 black around the orifice, greenish in the interior. Closely allied to 

 the F. glaucopsis and alabastrites from the Cape Verde Is. (Eve.) 



Cape of Good Hope. 



F. conioides Rve., Conch. Icon. f. 95, Aug., 1850. — F. conoides 

 Sowb. Thes. Conch., p. 189, f. 51. 



%* 



Mediterranean and S. African etc., species. 

 F. nubecula Linne. PL 60, figs. 94, 95, 96, 97, 98, 99. 



Shell conical, ovate-oblong, summit a little in front of the middle. 

 Sculptured with numerous subobsolete, unequal radiating riblets. 

 Grayish, with rays of dull purple. Fissure oblong, parallel-sided,, 

 its breadth two-fifths of its length. Inside white or bluish-white in- 

 side the muscle-impression, the rest of a delicate green shade. Hole- 

 callus white or green, bounded by a brown line, which is often 

 obsolete. Margin acute, a little crenulated. 



The typical form is oblong, narrower in front, altitude not quite a 

 half of the breadth ; fissure oblong, about one-seventh the length of 

 the shell ; inside colored as above described, the muscle impression 

 rather distant from the margin (in this respect differing from the 

 South African species mutabilis and incarnata, which have the im- 

 pression near the margin), and the scar is narrow, generally deeply 

 impressed. The riblets of the outer surface are low, rounded, obtuse,, 

 often subobsolete. 



Length 22, breadth 14, alt. 6* mill. ; length of hole 3 mill. 



Length 25, breadth 15}, alt. 8 mill.; length of hole 3f mill. 



Length 24, breadth 16}, alt. 7} mill. ; length of hole 3} mill. 



Mediterranean and Adriatic Seas; Atlantic Ocean from the Gulf 

 of Gascogne and Mogador to Cape Verde Islands. 



Patella nubecula Linn. Syst. Nat. xii, p. 1262. — Fissurella nube- 

 cula L. Hanley, Ipsa Linn. Conch., p. 434, t. 4, f. 10. — Weinkauff, 

 Conchyl. des Mittelm. ii, p. 394. — Arad. et Ben. Conch. Viv. Mar. 

 della Sic, p. 128. — Buquoy Dautzenberg & Dollfus Moll, du 



