384 MOI.LUSKS OF THE GALAPAGOS STEARNS. 



breadth, 31.5 inillimetcrs. These proportions vary slightly in ditt'erent 

 individuals. 



({•Mills ONCHIDELLA (iray. 



31. Onchidella Steindachneri Sfiupcr. 



riato I.I, tifrurcs I, 5. 



Living ('xami)lcs, between tide marks. 



Charles Ishiud, A\)y\] S, six six'ciinciis (Mus. No. 122.518): Albemarle 

 Island, Ai)ril 10, 18.SS, one exanii)h> (Mus. No. 122517). 



A well-marked speeies; edge of mantle prettily fringed on the under 

 side with rather regularly placed trifoliale processes. Dorsum entirely 

 covered with closely set, rounded, granular papilla-, which also cover 

 thesnrfaee of Ihe wide mantle margin beneath, up to the edge of the 

 <'ree|>ing disk, ('olor dark giayish or smoky black above; dingy 

 whitish on the under side. Anal orilice posterior, central just behind 

 the end of the creeping <lisk? Respiratory orifice on the right side 

 near the vent. Sexual orilice anterior near the tentacle or oral append- 

 age, under the edge, on tlui riglit side. Length about 20, breadth 

 about 17 millinu'ters. These proportions vary somewhat in different 

 specimens. Some allowance must be made for the contraction caused 

 by the alcohol in both the above and <). Jjcsliri. 



Family SIPHONAKIIDiE. 



Genus SIPHONARIA Shy. 

 Subf^cuiis WILLIAMIA Moiitcrosato. 



32. Siphonaria CWilliamia) peltoides Dall. 



Beach shells. 



Hood Islaiul, two examples in fair condition (Mus. No. 1023C5); 

 previously detected in the Galapagos by Dr. Habel (Mus. No. 6041(1), 

 at which of the islands not stated. Dall* gives the range of its distri- 

 bution ncntherly as Monterey; it has since been detected near Cres- 

 cent ('ity, Cal., which adds about 370 miles to its northerly range. 



Family CONIDiE. 

 (Ji'iius CONUS \Annf. 



33. Coiius bruniieus (Gray) Wood. 



-|- C. diademus Sby. 

 -j- C. tiaratus Brotl. 



Nnnn'rous; beach shells. 



Hood, Indefatigable, andJames islands each lurnished many examples 

 of the typical form of bruiDieus. 



An exceedingly variable speci(\s in size, color, and sculpture. 



The uniformly brown-colored specimens ('. diddrniiis Sby. The 

 sharply sculptured and generally dark colored individuals (Sow., 



*Am, Jour. Concb., Vol. VI, 1870. 



