90 



Udbredelse: Maine, Massachusetts (Binney) — Jan Mayen, 

 10 — 15 Fvn. (Friele) — Spitzbergen (Friele). 



(71). Thracia obliqua^ Jeffreys. 



1 877. Thracia obliqua^ Jeffreys : Ann. Mag. Nat. Hist., ser. 4, vol. 



20, p.490. 



Vest- Grønland: 82'' 27' N.B. 61° 42' V.L. („Alert & Dis- 

 covery". Fossil). 



«A valve measuring an inch and six tenths in breadth by an 

 inch and one tenth in length. It is distinguishable from Thracia 

 ( Amphidesma) truncata of Brown, = T. myopsis.^ Beck, in having a 

 more oblique or twisted shape , a straight instead of rounded 

 margin in front, and a more gradual or less abrupt slope to 

 each side ; the truncature at the posterior side is broad and 

 regularly curved ; and the surface is puckered, as in Mya trun- 

 cata. It wants the flexuosity of T. pubescens, but resembles in 

 its outline that species more than T. truncata. T. septentrionalis, 

 Jeffr. {truncata of Mighels and Adams), differs in shape and 

 texture from all the above-named species. Having, however, 

 seen but a single valve, 1 will not insist on this constituting 

 a new species.» (Jeffreys I.e.). 



72. Thracia truncata, (Turton). 



1 822. Anatina tnmcata, Turton : Conch. Insul. Brit., p. 46, Tab. 4, 



Fig. 6. 



1842. Thracia myopsis , Beck; Møller: Index Moll. Groenl., 



p. 21. 



1851. — Couthouyi, Stimpson : Shells of New England, 



p. 23. 



1870. — myopsis^ Beck; Gould & Binney: Rep. Invert. 



Mass. 2 Ed., p. 71, Fig. 385. 



1877. — — — ; Mørch in Rink: Dan. Green- 



land, p. 440. 



