GLYPHIS. 211 



lets of somewhat larger size, having three smaller intermediate rib- 

 lets in each interval. 



The shell is solid, strong. Color whitish or grayish yellow, uni- 

 colored or having ill-defined darker rays or occasionally a concen- 

 tric band. Inside white, often with a concentric bluish zone ; bor- 

 der finely denticulate, the toothlets usually in pairs ; basal margin 

 more or less arched, the ends alone supporting the shell. Length 

 57, breadth 40, alt. 20 mill.; often smaller, L. 44, br. 29, alt. 16. 

 Mediterranean and A driatic Seas ; Cape Verde Is. 



F. Italica DEFR., Diet. Sc. Nat. xvii, p. 79, 1820. BUQ., DAUTZ. 

 & DOLLF., Moll. Mar. Rouss. p. 476, t. 53, f. 1-3. .F. costaria 

 DESK., Coq. Foss. Env. Paris, t. 2, f. 10-12, 1824. PHIL., Enum. 

 Moll. Sicil. i, p. 116, and of others. F. defrancia Rrsso, Eur. Merid. 

 iv, p. 258. F. neglecta DESH., Encyc. Meth. ii, p. 138, 1830, and 

 of authors generally. F. mediterranea GRAY in SOWB. Conch. 

 Illustr. f. 30. F. erassa and F. tedumpersicum O. G.-CoSTA, teste 



MONTEROSATO. 



This form, usually known as F. neglecta Desh., is larger than 

 other Mediterranean Fissurellidse. It differs moreover in the close 

 rounded riblets, decussated by very fine concentric striae. It is 

 widely distributed as a fossil (Miocene to Quaternary) in Europe. 



The mutations noted by Buquoy, Dautzenberg and Dollfus are 

 as follows: (1) conica Monts. (=elevata Monts. olim) ; (2) major 

 Fischer ; (3) minor Monts. ; (4) depressa Monts., very much flat- 

 tened ; (5) latereplicata Monts., an exaggerated form of the preced- 

 ing, the lateral borders being upturned. 



G. ALTERNATA Say. PI. 37, figs. 50, 51, 52, 53; pi. 61, figs. 24, 



25. 



Shell oval, elevated, conical, front slope straight or concave, back 

 slope convex ; surface closely, finely latticed by radiating riblets 

 (every fourth one slightly larger) and concentric elevated lirulse or 

 laminae, which form little scales where they cross the radiating rib- 

 "lets. 



Color grayish-yellow or buff, unicolored or radiately striped with 

 pink, black or brown ; the stripes are eight in number, often broken 

 into angular spots ; sometimes unicolored blackish specimens occur. 

 Summit in front of the middle, more or less curved forward. Fis- 

 sure key-hole-shaped, not encircled by a dark line. Inside white ; 



