SYNDOSMYA. 55 



and torches of bright red about the hinge; a broad 

 anterior lateral tooth. 



T. halustina : very round, with narrow briglit-red rays. 



T. donacina : rather long and obhque, with the posterior side 

 very short and truncated; colours pink and yellow, very 

 brightly rayed with red. 



T, jii/gmcea : very similar to T. donacina^ but small and more 

 obtuse. 



T. incarnata : slightly striated, oblong, beaked at the hinder 

 side, and flesh-coloured. 



T. solidula: red, thick, round, nearly as broad as long, 

 slightly beaked, and with a strong fold behind. 



T. tenuis : smooth, flat, oval, small, slightly beaked behind, 

 flesh-coloured. 



T./ahula : small, brownish in the middle, rounded anteriorly, 

 and rather contracted and beaked behind. 



T, proxima : small, round, nearly white, with an epidermis. 

 It differs not very widely from T. solidula. 



lY. Syndosmya. — The principal difTerence between this ge- 

 nus and Tellina is, that the elastic part of the ligament 

 is received in a spoon-shaped pit within the shell; 

 there are lateral teeth in one valve. The animal is very 

 similar to that of Tellina, and, like that genus, its ha- 

 bits are to burrow in sand or mud ; the foot, having a 



