Tellinidae and Semelidae 83 



and abrupt with submarginal undulation, posterior area flexuose; 

 right valve with two cardinal teeth, one in left; no lateral teeth; 

 interior tinted like exterior; pallial sinus partly confluent, three 

 millimeters from anterior muscle scar. 



Genus STHKilLLA Turton, 1822 

 Strigilla carnariai-'-' (Linne) PI. 43, fig. 306 



Alt., 12.5; length, 15 mm. Shell smooth, glossy, pale rose color, 

 deepest over umbos; slightly inequilateral, umbos rounded; small 

 lunule; margins smooth and rounded; surface sculpture of extremely 

 fine striae, evenly radiating in central area, oblique over anterior 

 area, meetmg central stnations in acute angles, oblique and wavy 

 over posterior area; two cardinal and two lateral teeth in right valve, 

 one cardinal and two weak laterals m left valve; interior deep rose- 

 pink; upper border of pallial sinus makes a continuous line between 

 anterior and posterior muscle scars. 



Genus TKLLIDOKA (Morcli MS.) H. and A. Adams, 1856 

 Tellidora cristatai^o (Recluz) PI. 16, fig. 101 



Alt., 22; length, 26 mm. Shell shining white, much flattened, 

 right valve the more convex; thin brownish periostracum; trigonal, 

 with extremely convex ventral margin, anterior border excavated, 

 posterior border almost straight; the anterior and posterior borders 

 of each valve bear a series of sharp serrations; umbos acute, almost 

 central; concentric incremental growth somewhat lamellate and 

 terminating in the marginal serrations; lamellations stronger toward 

 margin; pallial sinus wide, partly confluent. 



Family SEMELIDAE 



The mollusks of this family are native to all warm seas, few of 

 its members have become adapted to cold water. One Atlantic species 

 of the genus Abra has a range from the Atlantic Ocean to the West 

 Indies, at increasingly greater depths toward the south. 



The animals live deeply buried in sandy mud, usually at mod- 

 erate depths, and are able to desert the old burrows and bury them- 



^■^■^ Lat., strigil, a scraping tool; carnis, flesh, 

 1*0 Lat., crista, crest. 



