1&2 VENERID^. 



Subfamily TAPESIN^. 



Shell oblong, transverse ; cardinal teeth compressed; laterals, 

 when present, simple. Siphons separate ; foot lanceolate, bys- 

 siferous. 



Tapes, Miihlfeldt. 



Etym. — Tapes, tapestry. 



Byn. — Omalia, Ryck., 1856. Parembola,Romer. 



Dislr. — 78 sp. Norway, Britain, Black Sea, Senegal, Brazil, 

 India, China, New Zealand ; low-water — 100 fathoms. — Beechy. 

 Fossil, 6 sp. Cretaceous — ; Britain, France, Belgium, Italy. T. 

 litterata, hinn. (cxiv, 35). 1. geogi^aphica. Chemn. (cxiv, SG"*. 



Shell oblong, umbones anterior, margins smooth ; teeth three 

 in each valve, more or less bifid ; pallial sinus deep, rounded. 



Animal spinning a byssus ; foot thick, lanceolate, grooved : 

 mantle plain or finely fringed ; freely open in front ; siphons 

 moderate, separate half-way or throughout, orifices fringed, and 

 cirri simple, branchial ramose ; palpi long, triangular. 



The animal is eaten on the southern Eui'opean coasts ; it buries 

 in the sand at low-water, or hides in the crevices of rocks, and 

 roots of sea-weed. 



AMYGDALA, Romcr. (Cuueus, Dacosta.) Radiately striate or 

 decussate. T. decussata, Linn. 



MYRSus, H. and A. Ad., 1858. (Metis, Ad., 1857.) Concen- 

 trically wrinkled. T. corrugata.^ Desh. 



paratapes, Stolicz., 1870. (Textrix, Romer, not Blachwall or 

 Sundewal, 1833, = Arachnoidea.) Shell much elongated, com- 

 pressed, outer surface smooth. T. textrix, Chemn. 



HEMiTAPES, Rb'mer. Shell inflated, solid, ventricose, especially 

 at the umbones, which are incurved, more or less narrower pos- 

 teriori}' ; outer surface smooth. T. piriguis, Chevavi. 



PuLLASTRA, Sowb. 1827. 



Distr. — Eastern seas. P. Malabarica, Chemn. (cxiv, 37). 



Shell transverse, oblong, oval and sometimes subtrigonal ; 

 hinge composed of three contiguous cardinal teeth, more or less 

 divergent, sometimes bifid or simply channeled at the summit ; 

 beaks directed forward ; margins simple ; anterior muscular 

 impression oval, posterior larger and rounded ; pallial impression 

 rather distant from the margin, with an oval, shallow sinus. 



Animal with membranous, transparent mantle, the margins 

 plain ; siphons partly separate, unequal, the extremities with 

 small tentacles, branchial siphon largest and longest ; foot 

 elongated, compressed, triangular, sometimes byssiferous ; 

 branchise unequal, united behind the foot and around the anal 

 siphon ; mouth oval, small. 



