132 THE NAUTILUS. 
Indies (reversed shell, a dextral one figured by Favanne, 
pl. 35, f. 1). Martini, Conch. Cab. III, f. 916. + Turbi- 
nella rapa Lamarck, 1822. 
VoLuTA scaBRIUscuLA H., p. 85, No. 1913. Martyn, f. 21. 
==Mitra sphaerulata Martyn, 1784. 
Votuta scaFa S., p. 41, No. 969 a; p. 186, No. 3039. Guinea. 
Adanson, t. 3, f. 2. Martini, Conch. Cab. III, t. 70, f. 
764. -+ Voluta porcina Lamarck, 1811. 
VOLUTA VIRESCENS S., p. 26, No. 610; p. 186, No. 3020; p. 174, 
No. 3751. Guinea. Martini, Conch. Cab. III, f. 932, 
933. + Voluta polyzonalis Lamarck, 1811. 
TWO NEW SOUTH AMERICAN SHELLS. 
BY W. H. DALL. 
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 0. 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 
