CLASS PELECYPODA 
37 
Malletia pacifica Dali, 1897. 
Plate 13, fig. 17. 
Nat. Hist. Soc. Brit. Col. Bull. No. 2:11; pi. 2, fig. 11. 
Shell thin, inequilateral, gaping, elongate-ovate, with a brilliant 
olive-yellow periostracum, showing zones of lighter and darker color, and 
smooth inflated valves; beaks low, anterior nearly reaching the anterior 
third; surface marked by obsolete incremental lines, and behind, with 
obscure radial depressions; base arcuate, anterior end acutely rounded, 
anterior dorsal margins vertical, pouting, somewhat gaping; anterior part 
of the shell more inflated, posterior more compressed, posterior ventral 
margin waved, posterior end obscurely obliquely truncate, posterior dorsal 
margin straight with a long very narrow black ligament, which is con¬ 
tinuous between and for a short distance in front of the beaks; pedal and 
siphonal gape conspicuous; interior bluish white, pallial sinus extremely 
shallow; hinge plate very narrow, the anterior teeth larger, much more 
crowded, about 12 in number; posterior teeth very small, about 45 in all. 
Length, 30; height, 17; diameter, 10 mm. (Dali.) 
Type in U. S. N. M. Type locality, Clarence Strait, Alaska. 
Range. Chignik Bay, Alaska, to Monterey, California. 
Malletia faba Dali, 1897. 
Plate 13, fig. 16. 
Nat. Hist. Soc. Brit. Col. Bull. No. 2:10; pi. 2, fig. 10. 
Shell ovate, smooth, slightly inequilateral, inflated, thin, covered with 
yellowish olive, brilliantly polished periostracum; beaks full, but not 
elevated, nearer the posterior end; anterior end rounded, dorsal and ven¬ 
tral margins nearly parallel, posterior end shorter, slightly more pointed; 
surface smooth or marked only by feeble lines of growth; a feeble im¬ 
pressed line may be regarded as the boundary of a lanceolate escutcheon, 
which is not impressed; internally bluish white, a small high pallial sinus 
reaches nearly to the vertical of the beaks; hinge plate very narrow, the 
ligament very small and black, is wholly external and posterior; there 
are about nine small posterior teeth, the anterior teeth are still smaller and 
shorter and number about 32. Length, 22.5; height, 13; diameter, 9 
mm. (Dali.) 
Type in U. S. N. M., No. 122569. Type locality, off Sea Lion Rock, 
Washington. 
Range. Queen Charlotte Islands, British Columbia, to Lower Cali¬ 
fornia. 
Malletia flora Dali, 1916. 
Proc. U . S. N. M., 52:400. 
Shell small, thin, inequilateral, smooth, polished, pale olivaceous, 
somewhat compressed, the beaks at 4 mm. behind the anterior rounded 
