452 PROCEEDINGS OF THE ACADEMY OF [1896. 



not channelled ; operculum smooth, whitish, angulated only at the 

 upper extreme ; alt. of shell 2.3, max. diam. 3.3 mm. 



This was the first species of the family to be reported from the 

 Galapagos. The type is not known from the west slope of the 

 Andes, though it would be rash to infer that it may not yet be found 

 there ; it is present in the Panamic province. Though first obtained 

 from Chatham Island Herr Reibisch writes that he has now received 

 examples from the Albemarle Island, 



An examination of the radula shows points of interest. The rha- 

 chidian tooth has a distinct cusp which is wanting in the Helicinas 

 heretofore figured; there are one major and three minor laterals. 

 The inner pair are channelled on the back and have a simple out- 

 wardly directed cusp ; the next is smaller, with the cusp pointing 

 inward. The major lateral appears very differently according to 

 the position in which it is viewed. In the normal position the cusp 

 is large, short with about seven subequal denticles, the base is plain 

 and without accessory projections ; the uncini are numerous, close- 

 set, simple and very small. Formula 1 . 



X y 3'3 ?■ X 

 Auricula stagnalis Orbigny. 



Auricula stagnalis Orbigny, Mag. de Zool., 1835, p. 23, No. 3. 

 Auricula gratiidina Anton, Verz., p. 48, 1839. 

 Auricula papillifera Kiister, Auric, p. 25, t. 3. figs. 9, 10, 1844. 

 Ellol>i7t?n grafiuiimrm H. & A. Adams, P. Z. S., 1854, p. 7. 

 Ellobium sta^nale H. & A. Adams, Gen. Rec. Moll., ii., p. 238 ; Wimmer, 

 Sitzb. k. Akad. Wiss., Wien, Bd. Ixxx, p. 44, No. 87, 1879. 



Panama and Guayaquil, Orbigny and Adams ; Tumaco Island, 



Cuming ; Bindloe Island, Habel fide Wimmer. 



Melampus trilineatus C. B. Adams. 



Auricula trilitteata Adams, Pan. Shells, Ann. Lye. Nat. Hist., N. Y., Y, pp. 

 436, 543, 1852. 



Melampus trilineatus Pfeiffer, Men. Auric, p. 44, 1856; Wimmer, Sitzb. k. 

 Akad. Wiss., Wien, Ixxx, p. 44, 1879. 



Panama, Adams; Hood Island, Habel, fide Wimmer. 



Tralia panamensis C. B. Adams. 



Auricula panamensis Adams, Pan. Shells, Ann. Lye Nat. Hist., N. Y., V, 

 pp. 433, 542, 1852. 



Tralia panamensis H. & A. Adams, P. Z. S., 1854, p. 10 ; Wimmer, op. cit., 



p. 45,1879. 



Hood and Charles Islands, Habel, fide Wimmer; Panama and 

 Taboga, C. B. Adams; Cocos Island, U. S. Fish Commission. 



Genus PEDIPES (Adanson) Scopoli. 

 Pedipes (Adanson) Scopoli, Intr. Hist. Nat., p. 392, 1777. 



