﻿I36 SMITHSONIAN MISCELLANEOUS COLLECTIONS [VOL. 4/ 



canal, prominent heavy body-callus, feebly sculptured or smooth, the 

 callus reflected over the pillar and body whorl, the margin of the 

 columellar reflection free and entire, the outer lip denticulate. The 

 nuclear whorls conical but very small. Operculum " triangular with 

 submarginal nucleus " fide Tryon. Sculpture nodulose-reticular. 



The varices in this group are so swollen that the following whorl 

 is apt to become oblique on the axis and the whole spire is often 

 tortuous. Coloration nebulous, yellow, brown and white. 



PSubgenus Cumia Bivona, 1838. 



Type C. decussata Bivona, = Triton reticulatus LUainville, Medi- 

 terranean. 



Shell small, delicate, spire not torticular; protoconch minute, 

 smooth, lying on a planorboid nepionic shell with deep sutures and 

 rounded whorls. Operculum elongate-ovate with apical nucleus. 

 Varices numerous, irregular. Colors as in Cohtbraria s. s. 



Section Maculotriton Dall, nov. 



Type Triton bractcatus Hinds, Polynesia. 



Shell ribbed axially and sulcate spirally ; apex obtuse, spire ele- 

 vated, with appressed sutures, varices inconspicuous, two or three 

 only. Nucleus of two or three whorls; coloration of black and 

 white, usually conspicuously articulated ; operculum ? 



Section Moiiustiolum Dall, nov. 



Type Triton swifti Tryon, West Indies. 



Shell small, with elevated spire and a single terminal varix ; 

 nucleus with the protoconch immersed in the first nepionic whorl 

 leaving an apical pit ; next later whorls axially ribbed, the ribs obsolete 

 on the subsequent whorls of the adult; coloration as in Cohtbraria 

 s. s. ; sutures appressed ; operculum elongate-oval, with apical nucleus. 

 Animal with slender tentacles, the eyes prominent on their outer 

 bases ; the verge sickle-shaped and recurved on the back of the neck ; 

 the radula long, carrying teeth of a type closely similar to those of 

 Pisania maculosa Lamarck, and P. fitsiforniis Blainville, as figured 

 by Troschel, and with the dental formula J.^.-J, the base of the 

 rhachidian tooth not excavated in front. 



Section Caducifer Dall, nov. 



Type Triton truncatus Hinds, Polynesia. 



Shell small, subcylindric, the upper fourth of the spire self-ampu- 

 tated in the adult; a single terminal varix; sculpture of axial ribs and 

 spiral threading, sutures appressed. Nucleus? Operculum? 



