148 AMERICAN JOURNAL 



Tectum [lotMd) fulva, H. and A. Adams, Gen. Rec. 



Moll. vol. i, p. 461, pi. lii, fig. 6. 

 Techira fulva, Jeffreys, Br. Conch, vol. iii, p. 250. 

 lothia fulva, Gray (not Forbes), Syst. An. Figs. Moll. 



An. p. 93, 1854 ; Guide to Moll. p. 172. 

 Patella rubella, 0. Fabr., Fauna Gronl. p. 386, No. 883. 

 Pilidium ruheUum, Stimpson, Check List East Coast 



Shells, No. 312. 



*S^. ch. — Shell patelliform, orange-fulvous, rarely paler, or 

 even white ; apex anterior, pointed, prominent. Sculpture, 

 elevated radiating strige, crossed by concentric imbricating lines 

 of growth, forming reticulations of greater or less strength, and 

 sometimes almost entirely absent. Interior smooth, polished, 

 particularly European specimens. Long. '30, lat. '18, alt. "10 

 in. Apical defl. 108°. Ten specimens examined. 



Soft parts. Body whitish ; no eyes ; tentacles short, stout, 

 foot oval. Rostrum provided with short triangular appendages. 

 Mantle entire fringed with short transparent cilia. No external 

 branchioe. (Jeffreys and Loven.) 



Rhachidian tooth long, narrow rhomboidal, provided with a 

 heavy central cusp and two small denticles. Laterals with slen- 

 der shafts pointed at the bases ; cusps broad, obliquely bent, 

 striated beneath. (Loven.) 



I have not been able to obtain specimens of the soft parts of 

 this species, and quote Jeffreys and Loven. 



Patella rubella, 0. Fabr., seems to be a coarser, paler variety 

 of the above, from authentic specimens. 



N, B, — This species has been referred to the Tecturidce by 

 Jeffreys, apparently under the misapprehension that the denti- 

 tion resembled the typical Tectura, from which it is widely re- 

 moved. He states that Tectura has elongated and hooked later- 

 ' als, and two central or rhachidian teeth; which is a mistake. 



The dental formula of Tectura is 3/\3 in the diagonal series, 

 and there are no central teeth. It almost identically agrees with 

 Acmoea fnitra, Esch., which, according to Philippi, is (from the 

 original specimen) the type of Eschsholtz' genus Acma^a, his 

 Acmoea mammilaris being an eroded specimen of the same species. 

 It is certainly not the same as Sowerby's Lottia pallida, which 

 is certainly the same as Scurria scurra, d'Orb., from which *S'. 

 mitra is likely to differ generically. It does not possess the re- 

 markable frills between the mantle edge and the foot, figured 

 by d'Orbigny and particularly noticed by Gray (Guide Moll. p. 

 172). 



