202 PROCEEDINGS OF THE ACADEMY OF [April, 



Metis postrema n. sp. 



This species is closely related to M. chipolana and M. efferta, but 

 differs from both by its relatively greater length. 



Length 36, alt. 28.7, diam. about 14 mm. 



Type No. 2760, A. N. S. P. Two other specimens. 



Whether further series will show that these three supposed species 

 intergrade we cannot tell. With the material before us, they seem 

 sufficiently distinct. All were labelled Macoma constrida Brg. by 

 Gabb. It was a wild shot, even for him. 



Labiosa (Eaeta) gabbi n. sp. 



Roeta canaliculata Say, Gabb, Trans. Amer. Philos. Soc, XV, 1873, p. 248. 



The shell is oval-subtriangular, the beaks nearer the anterior end; 

 sculptured with small concentric ribs which are weaker in the middle, 

 where there is a slightly depressed, quite inconspicuous, wedge-shaped 

 area radiating from the beaks. Beaks small, turned forward a little, 

 smooth. Posterior end rounded, somewhat compressed, the contour 

 in dorsal view being somewhat wedge-shaped. Hinge not exposed. 



Length 28, alt. 2.3, diam. 13.8 mm. 



Type No. 2675, A. N. S. P. 



As the shape, sculpture and size differ conspicuously from L. 

 canaliculata, it is not easy to account for Gabb's identification. 

 It is also obviously unlike L. alta (Conr.). Besides the specimen 

 mentioned by Gabb, five others were found in unassorted material. 



