MOLLUSKS. 45 



softened in water only — had the plates so much affected by the decorti- 

 cation of the whole jugular portion that I was unable to extract them 

 in a perfect condition. However, all the characters could be made out 

 except the mucro, which, judging by the remaining strise of growth, 

 must have been central, or nearly so. (Carpenter MS.) 



HELICIDiE. 

 Helix (Hyalina) hookeri. 



Helix hookeri, Pfr. Mon. Hel. iii, 88, No. 531. 

 Helix hooTceri, Eeeve, Conch. Icon. 208, n. 1474. 



Mus. ]^o. 11904. 



Kerguelen Island, Hooker, Dr. Kidder. Gregarious about and under 

 stones. Occasionally the shell of this species appears to be partly mem- 

 branous, aud in drying, from this cause, the spire is frequently abnor- 

 mally flattened. 



SIPHONARIID^. 



SiPHONABIA TRISTENSIS. 



Siplionaria tristensis, Sby. Gen. Sh. f. 3. ; Dall. Am. .Tourn. Conch, vi, 1870. 

 Sijyhonaria lessoni, Blainv. teste Eve. Ic. v., fig. 23, a, 6. 



Mus. No. 11905. 



Tristan d'Acunha, Eve. Orange Harbor, Patagonia, United States 

 Exploring Expedition; Kerguelen, Dr. Kidder; abundant between tide- 

 marks. 



ACEPHALA. 



LASEID^. 



Lasea rubra, Mont. 

 Mus. Ko. 11906. 



Kerguelen Island, Dr. Kidder, four specimens ; with mussels. Dis- 

 tribution worl^-wide. These individuals are rather larger than most 

 northern specimens. 



EEPTONID^. 



Lepton parasiticum, n. s. 

 Mus. Fo. 11907. 



Shell small, elongate ovate, inflated, thin ; beaks nearly central, not 

 prominent, surface shining, but not polished, with the texture of a Pan- 

 dora. Shell white, hardly sculptured, but under a high magnifying 



