MEGATEBENNUS. 185 



Das Durchbohrte Schildchen Meuschen, Conchyliologische Briefe, 

 in Der Naturforscher, 18te Stiick, p. 11, t. 2, f. 3, Halle, 1782.— 

 Patella scutellum Gmel. Syst. Nat. xiii, p. 3731. — Fissurella scutel- 

 lum Gray, Krauss, Die Siidaf. Moll. p. 63, 64. — Fissurella Man- 

 tula Lam., Reeve, Conch. Icon., f. 36, Aug. 1849. — Fissurellidea 

 hiantula Lam., Sowb. Thes. Conch., iii, p. 202, f. 193, 194, 195.— F. 

 hiantula of some other authors, but not of Lamarck, nor ofH. & A. 

 Adams. 



The confusion in the books is so great that no course seems open 

 except an appeal to the original authors. Gmelin cites only one 

 figure for his Patella scutellum (exclusive of varieties); that one is 

 Meuschen's excellent and unmistakable illustration, with which 

 the brief description also agrees, and which represents the F. 

 hiantula of Reeve and others. This is not the F. hiantula Lam., 

 for Lamarck refers to Bora's vignette (Test. Mus. Cses. p. 414, fig. 

 F.) as an illustration of his shell. This vignette represents F. 

 megatrema Orb. (Note especially the characteristic white border !): — 

 Certainly not the hiantula of Reeve and modern authors. Sowerby 

 (Conchol. Illust.) refers hiantula Lam. to Pupillia aperta — a wholly 

 improbable supposition. 



M. chemnitzii Sowerby. PI. 36, fig. 90. 



Shell ovate, attenuated anteriorly, rather depressed, peculiarly 

 compressed at the sides, lifted at the extremities ; radiately ribbed, 

 ribs rugged, unequal, obsoletely nodose, rather swollen here and 

 there ; orifice large, oval ; stained and rayed with olive-green and 

 purple-rose. (Rve.) 



Benguela, West Africa. 



F. chemnitzii Sowb., P. Z. S. 1834, p. 126 ; Conchol. Illust., f. 55. 

 — Reeve, Conch. Icon., f. 1. — Fissurellidea chemnitzii Sowb. Thes., 

 p. 202, f. 29, 192. 



M. sella Sowerby Jr. PI. 62, fig. 8. 



Shell short, narrowed in front, sides a little compressed, ends 

 much elevated ; fulvous-reddish, minutely striated, grayish inside ; 

 margin smooth, circumscribed by a purple callus. An interesting 

 saddle-shaped shell, which has the pinched-up character of F. hian- 

 tula [=.F. scutellum Gm.] etc., but is much shorter. It has the ends 

 raised more than any other species. (Sowb.) 



South Africa. 



Fissurellidea sella Sowb. Thes., p. 203, f. 297. 



