132 THE NAUTILUS. 



Indies (reversed shell, a dextral one figured by Favanne, 



pi. 35, f. 1). Martini, Conch. Cab. Ill, f. 916. -\-Turbi- 



nella rapa Lamarck, 1822. 

 VOLUTA SCABRIUSCULA H., p. 85, No. 1913. Martyn, f. 21. 



Mitra sphaerulata Martyn, 1784. 

 VOLUTA SCAFA S., p. 41, No. 969 a; p. 136, No. 3039. Guinea. 



Adanson, t. 3, f. 2. Martini, Conch. Cab. Ill, t. 70, f. 



764. -f Valuta porcina Lamarck, 1811. 

 VOLUTA VIRESCENS S., p. 26, No. 610; p. 136, No. 3020; p. 174, 



No. 3751. Guinea. Martini, Conch. Cab. Ill, f. 932, 



933. -f- Valuta polyzonalis Lamarck, 1811. 



TWO NEW SOUTH AMERICAN SHELLS. 



BY W. H. BALL. 



A bunch of Gorgonians was recently received from the Pau- 

 lista Museum, San Paulo, Brazil, which were growing on bi- 

 valve shells. The latter were separated valves often in good 

 condition. The locality is San Sebastian Island off the south- 

 ern coast of Brazil. 



Among them was a Macoma-like shell which appeared to be 

 new. 



The subgenus Scissula includes species like T. decora Say, 

 which have the hinge of Angulus and an external oblique sculp- 

 ture of incised lines. The present shell however has two deeply 

 bifid teeth in the right and one in the left valve with no trace 

 of a lateral lamina in either valve. It therefore bears the same 

 relation to Macoma, subgenus Psammacoma as Scissula does to 

 Angulus in the Tellina group. I propose therefore to institute a 

 new section for it. 



PSAMMACOMA (TEMNOCONCHA) BRASILIANA n. sp. 



Shell white, equivalve, subequilateral, thin, compressed, 

 dorsal slopes subequal; anterior end broadly rounded, posterior 

 end obscurely obliquely truncate but hardly angulate at the 

 junction with the broadly arcuate base; sculpture of incremental 

 lines upon which are impressed sharp regular grooves about 



