178 
MARINE SHELLS OF WEST COAST OF NORTH AMERICA 
surface sculptured only with faint incremental lines; hinge normal, strong 
for the size of the shell; pallial sinus discrepant, in the right valve small, 
gibbous, short, about two-thirds confluent below; in the left valve large, 
reaching nearly to the anterior adductor scar, and three-fourths confluent 
below. Length, 14; height, 9; diameter, 4 mm. (Dali.) 
Type in U. S. N. M., No. 108652. Type locality, Lituya Bay, Alaska. 
Range. Lituya Bay to Sitka, Alaska. 
SECTION REXITH/ERUS Conrad, 1869. 
Macoma indentata Carpenter, 1866. 
Plate 44, fig. 4. 
Suppl. Rept. Brit. Assoc., p. 639. Proc. Cal. Acad. Nat. Sci., 3 :208. 
M. t. “M. sectce” simili; sed postice valde rostrata, sinu inter plicam et 
regionem ventralem valde expansam indentato. Long. 2.20; lat. 1.40; 
alt. 0.56. ( Carpenter.) 
Like secta, juv., but beaked, indented, and ventrally produced. (Car¬ 
penter.) 
Shell of medium size, rather narrow, suboval, compressed, thin; um- 
bones slightly posterior to center; anterior end long and evenly rounded; 
posterior dorsal line straight; ventral line near posterior end indented, the 
posterior extremity being much projected and sharply rounded; fold 
prominent; ligamental area short, scooped out. (Arnold.) 
Type locality, San Pedro, California. 
Range. Santa Barbara, California, to Lower California. In the 
Pleistocene at San Pedro and San Diego; Pliocene, El Toro Ranch, Mon¬ 
terey County, and Griswold's, San Benito County, California. 
Macoma indentata tenuirostris Dali, 1900. 
Proc. U. S. N. M., 23:309. 
Differs from the typical indentata in being more elongated, with a 
shorter and more pointed posterior end and deeper flexure. Long. 56; 
alt. 33; diameter, 16 mm. (Dali.) 
Type in U. S. N. M. Type locality, San Pedro, California. 
Range. Santa Barbara Islands to San Diego, California. 
Macoma secta Conrad, 1837. 
Plate 44, fig. 8. 
Jour. Acad. Nat. Sci. Phila., 7:257. Thes. Conch., Tellina; pi. 65, figs. 245, 248. 
Shell triangular or subelliptical, equilateral, compressed, thin, smooth 
and polished, covered with a very thin shining yellowish epidermis; 
umbonal slope angulated; posterior extremity broadly and obliquely trun¬ 
cated; cartilage short, thick, inserted on an elongated oblique riblike 
callous; margin beneath the cartilage with an ovate gape, appearing as if 
