394 American Seashells 



Genus Echinochama P. Fischer 1887 

 Echinochmna cornuta Conrad Florida Spiny Jewel Box 



Plate 37g 



North Carolina to both sides of Florida to Texas. 



I to I % inches in length, quadrate in outHne and rather obese and heavy. 

 Lunule distinct and broadly heart-shaped. With 7 to 9 rows of moderately 

 long, stoutish spines, between which the shell is grossly pitted. Exterior 

 creamy-white; interior white or flushed with bright pinkish mauve. Attached 

 to a small pebble or broken shell by the right valve. Common from 3 to 

 40 fathoms, and commonly washed ashore. 



Echinochama arcinella Linne (True Spiny Jewel Box, pi. 37h) from the 

 West Indies to Brazil has 16 to 35 (commonly 20) radial rows of slender 

 spines. The shell is not as obese nor as heavy as cornuta. The subspecies 

 calif orjiica Dall (pi. 37e) is very similar, with slightly longer spines and with 

 a more compressed shell. It ranges from the Gulf of CaHfornia to Panama 

 in offshore water. 



Superfamily LEPTONACEA 

 Family LEPTONIDAE 



A group of small, fragile, inflated, translucent clams which are parasitic 

 or commensal on other marine creatures or are active crawlers like the gastro- 

 pods. Most species brood their young inside the mantle cavity. The family 

 is also named Erycinidae and Kelliidae. 



Genus Kellia Turton 1822 



Shell unsculptured, inflated and oval-oblong. Lateral teeth present. 

 2 cardinal teeth in the right valve. 



Kellia laperousi Deshayes La Perouse's Lepton 



Alaska to Panama. 



% to I inch in length, oval-oblong, rather obese and with small beaks 

 near the center. Shell fairly strong, chalk-white, but commonly covered 

 with a smooth, glossy, greenish to yellowish-brown periostracum which, 

 however, is commonly worn away in the beak area. Very common. Found 

 attached to wharf pilings among mussels and chama shells. 



Genus Lasaea Brown 1827 

 Shell very small, beaks nearer one end. Teeth the same as in Kellia. 



