CLASS PELECYPODA 
73 
SECTION DIBERUS Dali, 1898. 
Lithophaga plumula Hanley, 1844. 
Proc. Zool. Soc., p. 17. Descr. Cat.; pi. 24, fig. 28. 
Lit. testa L. canalifero simillima, sed extremitate antice minus obtusa; 
tegmine calcareo antico, crassiore, atque in parietibus confertis, sub- 
parallelis ordinato; parietibus cor ruga tis et (plumulas haud dissimilibus) 
versus marginem et marginem anticum utroque latere radiantibus. 
(Hanley.) 
Shell elongately cylindrical, posteriorly rounded, smooth, anteriorly 
attenuated, peculiarly roughly feathered. (Conch. Iconica.) 
Type in Museum Cuming. Type locality, Panama. 
Range. Monterey, California, to Patagonia. Also Atlantic. 
SECTION LABIS Dali, 1916. 
Lithophaga attenuata Deshayes, 1836. 
Plate 39, fig. 10. 
Anim. sans Vert., ed. 2, 7 :28. Philippi, Abb. u. Beschr.; pi. 1, fig- 6. 
Shell cylindrical, thin, posteriorly globose, then contracted and an¬ 
teriorly gradually attenuated, smooth or obsoletely malleated throughout; 
yellowish olive. (Conch. Iconica.) 
Type. The location of the type is not known to the present writer. 
Type locality, Chile or Peru. 
Range. Monterey to San Diego, California; Patagonia. 
SECTION MYOFORCEPS Fischer, 1886. 
Lithophaga aristata Dillwyn, 1817. 
Plate 39, fig. 2. 
Descr. Cat. Rec. Shells, 1:303. Wood, Index Test.; pi. 12, fig. 8, 1825. 
Shell sub-cylindrical, rounded at the hinge, and armed at the opposite 
extremity with two beak-like processes which cross each other. (Dillwyn.) 
Shell an inch long, and rather more than one-third as broad; generally 
of a dirty white, but sometimes brownish or fawn-coloured; the want of 
striae, and a beak-like process from the extremity of each valve, crossing 
each other like the mandibles of the Loxia curvirostra, distinguish this 
species from M . lithophagns , of which, however, Doctor Maton considers 
it to be only a variety. (Adanson.) 
Type. Neither the location of the type nor the type locality is known 
to the present writer. 
Range. La Jolla, California, to Peru. Also Atlantic. 
