Page:American Seashells (1954).djvu/531

Macoma yoldijormis Carpenter Yoldia-shaped Macoma Alaska to San Diego, California. % to %. inch in length, elongate, moderately rounded at each end and with a small, but distinct, twist to the right at the posterior end. Color a uniform, glossy, porcellaneous white. Rarely translucent with an opalescent sheen. Common from shore to 25 fathoms. Macoma carlottensis Whiteaves Queen Charlotte Macoma Arctic Ocean to Lower California. About I inch in length, extremely fragile, inflated and with a very short, inconspicuous ligament. Color translucent-white with a thin, greenish, glossy periostracum. This species was named inflatula Dall at a later date. Macoma brota Dall Brota Macoma Figure 88a Arctic Ocean to Puget Sound, Washington. 3 inches in length, moderately elongate, moderately inflated and rather thick-shelled. Beaks % toward the posterior end. Resembles calcarea whose pallial sinus in the left valve, however, is more elongate, not as high and generally reaches nearer the anterior muscle scar. M. brota is larger and more truncate posteriorly than that species. Common. Macoma planhisciila Grant and Gale Grant and Gale Macoma Plate 30t; figure 88h Arctic Ocean to Puget Sound, Washington. About I inch in length. Extremely similar to calcarea, but porcellaneous, with a glossy, yellowish periostracum and more oval in shape. This species was thought by Dall and others to be "carlottejisis Whiteaves." Genus Gastrana Schumacher 1817 Subgenus Meter omacovia Habe 1952 Gastrana irus Hanley Irus Macoma Figure 88e Bering Sea to Los Angeles, California. Japan. Commonly 1% inches in length (rarely 3); oval-elongate, moderately inflated, very sHghtly twisted, if at all, at the posterior end. Pallial sinus in left valve almost reaches the bottom of the anterior muscle scar. Beaks slightly anterior. Common in Washington and Oregon. Formerly known as inqiiinata Deshayes.