NO. 2 ROST: THE FAMILY ARCIDAE 211 



arcinae, Trinacriinae, and Noetiinae. This arrangement is not used in 

 the present paper (see discussion by Reinhart, 1943, pp. 5 and 76). 

 Frizzell (1946) also gave the subfamily family rank, but retained it in 

 the superfamily Arcacea. 



Genus NOETIA Gray 1857 



Noetic Gray, Ann. and Mag. Nat. Hist., sen 2, vol. 19, 1857, p. 371. 

 Type of genus: Noetia triangularis Gray 1857 (by monotypy) = 

 reverse (Sowerby), fide Reinhart, 1935. 



Subgenus NOETIA s. s. 



Noetia (Noetia) reversa (Sowerby) 1833 

 Text-figs. 94 a-c 



Area reversa Sowerby, Proc. Zool. Soc. London, 1833, p. 20. 



Syn.: Noetia triangularis Gray 1857. 



Fig.: Reinhart, 1943, PI. 14, f^gs. 5, 7, 8. 



Type loc. : Tumbes, Peru ; 7 fms ; soft mud. 



Holotype: British Museum? 



Remarks: The general external appearance of the anatomy of this species 



resembles that of Noetia ponderosa (Say), which has been studied by 



Heath (1941; general appearance, PI. 18, fig. 1). In Noetia reversa^ 



the labial palps are relatively larger. Besides having two large anal 



papillae placed as in N. ponderosa (Heath, 1941, PI. 19, fig. 2), N. 



reversa has a papilla or flap (not always visible) in the opening of the 



anus. The mantle margin is unpigmented. The teeth are striated on 



both sides but the top is smooth. 



Occurrence: Noetia reversa was dredged by the Velero III and Velero 



IV in depths down to 24 fms, on sandy or muddy bottom. Hertlein and 



Strong (1943) report it down to 40 fms. Reinhart (1943) gives its 



habitat as intertidal. 



Distribution: Off Bahia Concepcion, Gulf of California, to Peru. 



Genus SHELDONELLA Maury 1917 



Sheldonella Maury, Bui. Amer. Paleontology, vol. 5, no. 29, 1917, p. 



166. 

 Type of genus: Noetia {Sheldonella) maoica Maury (by monotypy) ; 



Miocene, Dominican Republic. 



