398 AXEL A. OLSSON 



color often arranged in broad, concentric bands or in lighter shades of the 

 same. Surface smooth and polished but with a neat sculpture of fine, closely- 

 spaced concentric lines forming narrow ribbons spaced about six to eight 

 to a millimeter. The lunule is narrow and excavated, larger in the right valve, 

 the escutcheon similar. The tip of the pallial sinus does not reach the 

 anterior adductor by a short space, its lower limb largely confluent with 

 the pallial line. 



Length 51.7 mm., height 30 mm., diameter 11.7 mm, (Off Punta Malo,. 

 shrimpers. From Harry B. Johnson). 



Somewhat like E. rubescens but longer, easily separated by the features 

 of their respective pallial sinus. T. simulans has much heavier sculpture. 



Range — Mexico to northern Peru. Panama: Off Punta Mala (shrimp- 

 ers). Panama Canal Zone: Fort Amador. Ecuador: Mompiche; Santa Elena. 

 Peru: Zorritos. 



Subgenus PHTLLODELLA Hertlein and Strong, 1949 

 Type species by monotypy, Tellina {Phyllodella) insculpta Hanley. 



Like Eurytellina, s.s. but with the posterior-dorsal area squamosely 

 sculptured or roughened by small platelike scales. Pallial sinus deep, almost 

 reaching to the anterior adductor scar, its lower limb united with the pallial 

 line. 



Eurytellina (Phyllodella) Inscnlpta (Hanley) 



Tellina insculpta Hanley, 1844, Proc. Zool. Soc. London, p. 70. Hab. Chiriqui, West 



Colombia (Panama).— Hanley, 1846, Thes. Conch., vol. 1, Tellina, p. 289, No. 



128, pi. 60, fig. 136.— Sowerby, 1867, Conch. Icon., vol. 17, Tellina, pi. 37, fig. 



208. 

 Tellina {Phyllodella) insculpta Hanley, Hertlein and Strong, 1949, Zoologica, vol. 34, 



pt. 2, p. 87. — Hertlein and Strong, 1950, idem., vol. 35, pt. 4, pi. 1, fig. 15. 



Shell elongately oblong, compressed, thin or relatively solid, equilateral, 

 the dorsal margins sloping, anterior end rounded the posterior end angulated. 

 Internally and externally white, the surface sculptured with crowded, equi- 

 distant, concentric sulci (about four per mm.), and most minute posterior 

 radiating striate. Posterior area setoff by a weak angulation, its surface 

 roughened by small scales or interrupted delicate lamellae. Hinge as typical 

 of Eurytellina, the cardinal teeth being grooved. Pallial sinus deep, rather 

 high behind, and then descending, its end blunt and almost, but not quite, 

 touching the lower edge of the anterior adductor scar, its lower limb com- 

 pletely confluent with the pallial line. 



Length 33.6 mm., height 18.3 mm., convexity (both valves together), 5.8 

 mm. (Hertlein and Strong). 



Range — Guatemala to Ecuador. Guatemala: Champerico. El Salvador: 

 Santa Elena. Guatemala and El Salvador records by Hertlein and Strong; 

 Panama by Hanley. 



Genus TELLINIDELLA Hartlein and Strong, 1949 

 Type species by original designation, Tellinides purpureus Broderip and 

 Sowerby. Recent, eastern Pacific. 



Shell elongately elliptical, white or rose-pink, nearly equilateral, thin, 

 the beaks small and nearly median, the right valve a little more convex than 

 the left, usually flexed by a depressed zone across the middle, the left valve 



