Y8 Journal of the Mitchell Society [August 



Several specimens in the laboratory collection are recorded 

 as having been collected above Horse Island on mud bottom. 

 The animal, immature, is recorded from Pivers Island and 

 from Bogue Sound. A few other specimens have been taken in 

 the dredge in the vicinity of Beaufort. Valves are found rather 

 commonly. 



Area (Scapharca) campechensis Dillwyn. 



Area campechensis Dillwyn, Descr. Cat. Rec. Sh-, I., p. 288, 1817 (Syn. 

 partim exclus.), Jamaica and Carolina. 



Area pexata Say, Journ. Acad. Nat. Sci. Phila., vol. 2, p. 268, 1822; 

 Dall, Bull. 37, U- S. Nat. Mus., p. 40, 1889. 



Scapharca (Argina) campechensis, Dall, Trans. Wagner Inst. Sci., 

 vol. 3, pt, 4, p. 650, 1898. 



Small examples have been dredged in Bogue Sound; one 

 specimen in channel south of Green Rock. As many valves are 

 in the laboratory collection, further search will probably reveal 

 good collecting grounds. 



FAMILY PINNID^. 

 Genus Atrina Gray. 



Atrina rigida (Dillwyn). 



Pinna rigida (Solander MSB.) Dillwyn, Cat, p. 327, 1817. 

 Atrina rigida, Dall, Trans. Wagner Inst. Sci., vol. 3, pt. 4, p. 663, 1898; 

 Grave, B. H-, Bull. Bur. Fish., vol. 29, p. 411, 191 1. 



The species is fairly abundant. The usual collecting ground 

 is in the vicinity of Pivers Island. The form may be found at 

 about low water mark. The valves usually project a short dis- 

 tance above the surface of the ground. 



The anatomy and physiology of this species have been made 

 the subject of a report by Grave, loc. cit. 



FAMILY PTERIIDiE. 



Genus Pteria Scopoli, 1777. 



Pteria colymbus (Bolten). 



Pinctada colymbus Bolten, Mus. Boltenian., p. 167, 1798. 



Avicula atlantica, Dall, Bull. 37, U. S. Nat. Mus., p. 36, 1889. 



Pteria colymbus, Dall, Trans. Wagner Inst. Sci., vol. 3, pt. 4, p. 670, 1898. 



