PROCEEDINGS OF THE NA TtONAL M USE UM. 187 



Tres Marias (Ko. ;W15L», LT. S. N. M.) ; La Paz, Capt. Foi rer (No. 32151, 

 IL S. N. M.); also at Sta. Margarita Island (beach) Albatross. 



PURPURA TRIANGULARIS, ]U m i ii v i 1 1 e. 

 Examjtles. Tjoreto. 



MONOCERA8 TUBERCULATUM, (ir:iy. 

 -J- Purpuni miiricata, (Jkav. 



One example from each of the following j)laces : 



Tres Marias, Fisher (No. 60012, U. S. N. M.), and La Paz, Capt. Forrer. 

 Sta. Margarita Island, Albatross, three beach shells. This species ranges 

 southerly as far as Peru and extends also to the Galapagos Islands. 

 Two remarkable varietal specimens of this species have been brought 

 to my notice by Miss Cooke, of San Diego. One of these is 4i inches 

 long, the other nearly as large, and suggests a still greater range of 

 variation approaching the species known as 31. grande. The variability 

 exhibited by different specimens in the prominence of the horn has 

 been i)reviously mentioned. 



A young individual which I have examined, measuring only .76 inch 

 in length shows the horn; in another over 2 inches in length it is 

 barely perceptible. Gabb collected this at San Bruno, and two exam- 

 ples from this locality are contained in the IT. S. Nat. Museum; (No. 

 32154.) 



MONOCKRA.S LUGUBRIS, S o w e r 1. y . 



Several specimens. 



Tres Marias (No. 60017, U. S. N. M.). Ballenas Bay, Albatross, abun 

 dant; it occurs also at Sta. Margarita Island. Many examples of a 

 rather elongated, less solid and'robust form than those usually seen from 

 other localities in the general region. These have a rich purple mouth 

 merging into dark chocolate. The largest measui-ed long., 1.05 ; hit., 58 ; 

 long., 0.97; lat., 0.<U ; the latter the smallest. The above is rather a 

 variable species. 



SISTRUM FERRUGINEUM, Ke«ve. 



Common. Point Escondido; St. Josef Island; Los Aninms r>ay; 

 Lore to. 



Subfamily Coralliophilin^. 



CORALLIOPKILA (RHIZOCHILUS) NUX, Reevir^, ex Carpenter. 



=sil/Mrej; WMa;, Reevk, Couch. Icon. pi. 38, sp., 181. + i?. rts-^jem, Reeve. =1/. 

 (Ocinehra) mix, H. and A. Adams. Geuera VoL i, p. 75. ^Fwrpura contata, 

 Blainville. CorraJliopMla costafa, Blainville ; Cakpenter, Mazatlan shells, 

 p. 484. = Cuma costata, AucT. 



Four examples (No. 32167, U. S. N. M.). St. Jo.sef Ishind ; San Lucas 

 Cove; Tres Marias. 

 The spire which in young specimens is short becomes elevated 



