OF CONCHOLOGY. 23 



SlSTRUM MARGINALBUM, (Blain.) 



Purpura marginalba, (Blain.) Nouv. Ann. du Mus., 1832, 



p. 219. 

 Sistrum tuberculatum, (Ang. non Blain.) Proc. Zool. Soc, 



1867, p. 191. 

 The above species has been confounded with S. tuberculatum, 

 (Blain) by Mr. Angas and other authors. 



The . two agree as to sculpture, but may be readily distin- 

 guished by the characters of the aperture. They also differ in 

 shape. 



Nassa suturalis, Lam. 



Buccinum suturale, Lam. An. s. Vert, Vol. 10, p. 166. 

 Nassa intermedia, Dkr. Reise du Novar, p. 5, pi. 1, f. 2. 



The above species is found throughout the Papuan Islands, as 

 well as Australia, and varies widely. 



At some localities, it is almost colorless, excepting the trans- 

 verse lines, which are constant. 



The nodules on the upper part of the whorls are occasionally 

 much enlarged, passing down on to the last whorl, connecting it 

 with varieties of JST. hirta, Kien. The variety figured and 

 described in Voy. Novaria, is also noticed by Reeve in Con. Icon, 

 plate 2. 



In addition to the above, I have also received typical speci- 

 mens from Coll. of Novar. Exped. of Purpura distinguenda, Dkr., 

 collected at the Nicobar Islands, which 1 had previously received 

 from the Andamans and Red Sea. 



It is the variety of P. hippocastanum, Lam, described by M. 

 Deshayes as P. Savignii, (stellata, Bolt.) 



Ceritliium gibberosum, of the same work, should be compared 

 with C. patulum, Sow. 



Genus MITROIDEA, Pse. 



Mitroidea, Pse. Proc. Zool. Soc, *1865, p. 514. 

 Mauritia, A. Ad. Proc. Zool. Soc, 1869, p. 273. 



It is gratifying to learn of the discovery, at the Mauritius, of 

 a second species of the above peculiar form, for which Mr. Adams 

 proposed the above generic name. 



DOLIUM MELANOSTOMUM, Jay. 



The original locality given to the above species by Dr. Jay, 

 viz., Tonga or Friendly Islands, has not been confirmed, although 

 that group of Islands has been visited by several collectors during 

 the past feAv years. It does inhabit the Hawaiian Islands, 



