66 LEPETID.E. 



Lottia gigantea Gray, in Sowerby, Genera Sh., t. 1. — Reeve, 

 Concli. Syst., f. 1. — Carpenter, Amer. Journ. Conch, ii, p. 343. — 

 Dale, /. c. vi, p. 260, t. 15, f. 20 (animal and dentition). — Acmcea 

 scutum AuCT., not of Esch. nor d'Orb. — Tedurella grandis Gray, 

 Cpr., Smiths. Chk. List no. 176; Brit. Asso. Rep. 1861, p. 137.— 

 Patella kochi Philippi, Abbild. u. Beschreib. iii. Patella, t. 1, f. 1, 

 Jan., 1849. 



Young specimens (fig. 4) have fine, nearly obsolete radiating strii3e 

 and are roughened by low, obliquely radiately ribletsin front and at 

 the sides, which on the posterior half of the shell become broken 

 into low rounded tubercles or bosses arranged in curved rows 

 obliquely descending from the central line of the back. 



This is the largest and handsomest of the Californian limpets. 

 Philippi's excellent illustration of it seems to have been unknown to 

 writers on west coast shells. 



Family LEPETIDjE Gray. 



Lepetidre Gray, Guide Syst. Dist. Moll. B. M., p. 172, 1857.— 

 PatellidcB and Tecturidce, in part, of authors. 



Shell conical, patelliform, with subcentral or anterior apex ; sur- 

 face feebly sculptured, the edge smooth ; muscle-impression as in 

 Patella. Embryonic shell spiral. 



Animal without external branchi^ ; radula provided with a 

 rhomboidal cuspidate rhachidian tooth ; no lateral teeth ; uncini 

 slender, two each side, their cusps simple or fringed. Formula 

 2-0-1-0-2. 



It will be noted from the formula given that the side-teeth are 

 considered uncini rather than true laterals. The lateral teeth are 

 either aborted or represented by the lateral cusps of the rhachidian 

 tooth, which is, if this be the case, a compound body formed by 

 coalescence, as is the casein Phasianella (Orthomesus) virgo Aug. 

 I am not inclined, however, to believe this to be the case in Lepeta. 



The very different dentition of the genus Lepetella renders its 

 reference to this family somewhat doubtful. 



Synopsis of genera and subgenera. 



Subfamily Lepetix^e Dall. 



Radula having a large central tooth with several cusps, and two 

 side-teeth on each side. 



