206 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
elevation for the attachment of the ligament behind them. Ligament 
external and double. Cavity of the beaks profound; muscular and pallial 
cicatrices broad and well impressed; posterior muscular scar but little 
broader than the pallial impressions; siphonal sinus shallow, small. 
Length, 6; height, 3; diameter, 4 inches. (Gould.) 
Type locality, Nisqually, Puget Sound. 
Range. Puget Sound to San Diego, California. In the Pleistocene 
at Santa Barbara and San Diego, and the Pliocene at Santa Barbara, San 
Fernando and San Pedro, California. 
Panopaea generosa solida Dali, 1898. 
Plate 3, fig. 11. 
Trans. Wagner Inst., 3, pt. 4:831. 
Shell thin, short, inflated, the beaks nearer the anterior end, which is 
expanded and rounded in the pedal region; posterior end narrower, 
opposite margins not parallel; posterior hiatus smaller than in the type 
and somewhat recurved; nymph narrow, slender, somewhat longer than 
in the type; pallial sinus small, wide. Length, 160; height, 120; diameter, 
80 mm. (Dali.) 
Type in U. S'. N. M. Type locality, head of the Gulf of California. 
Range. Strait of Juan de Fuca to the Gulf of California. 
Genus PANOMYA (Gray) Adams. 
Shell solid, large, irregular, with a single cardinal tooth under the beak 
in each valve; the pallial line of unconnected, rounded impressions; the 
animal larger than the shell, with large, united siphons, diverging slightly 
at the tips and covered with a wrinkled coriaceous epidermis; a burrower 
in mud and gravel, never perforating stones. 
Type. My a norvegica Spengler. 
Distribution. Northern Seas, Mediterranean, Cape, Australia. 
Range in time. Inferior Oolite, United States, Europe, India. 
Panomya turgida Dali, 1916. 
Proc. U. S. N. M., 52:416. Bull. U. S. N. M. t 112; pi. 2, fig. 1. 
Shell very similar to the North Atlantic form but very much more 
capacious and larger. Length, 90; height, 60; diameter, 48 mm. (Dali.) 
Type in U. S. N. M., No. 151224. Type locality, Popoff Strait in the 
Shumagin group, Alaska. 
Range. Unalaska to the Shumagin Islands, Alaska. 
