242 BULLETIN OF THE 



mersed spire and both lips transversely grooved. It is probably not an Erato 

 at all, and is perhaps an Ovulactceon. The Erato vitellina cited by Marrat in 

 his list of shells collected by the party on board the Argo, undoubtedly came 

 from California, and it should have been so stated, as, placed as it was without 

 comment in a paper treating otherwise only of Antillean shells, it was certain to 

 lead to misconception. Although Mr. Marrat says it was a gift from Mr. Red- 

 field at Philadelphia, it follows the Abaco list without sufficient discrimination. 



Family TRIFORID^E. 

 Genus TRIFORIS Deshates. 



The character of the openings in this group seem to have been misunderstood 

 by Mr. Tryon in his recent monograph. He referred (Man., IX. p, 121) to 

 the " occasional preservation of a second canal upon the back of the body whorl, 

 showing the termination of a former aperture." I have never seen anything of 

 the kind in this genus, nor does Mr. Tryon figure any such formation. The 

 case of Triforis is not unlike that of Pleurotoma, except that in the latter group 

 the seclusion of the individual foramina is, so far as I know, never carried 

 quite so far as in typical Triforis. In both there is an aperture with a canal 

 and a presutural (doubtless anal) notch in the adult. In some forms of 

 Drillia, when fully mature, the notch becomes nearly tubular, but the siphonal 

 canal is not closed and seldom if ever has a tubular appearance. In Triforis, 

 however, the canal and anal opening, in certain species, become completely 

 tubular, and the last whorl after they are closed is continued for a quarter of 

 a turn more before the final adult aperture is completed. Between this state 

 of things and that in which the canal remains permanently open and the anal 

 notch becomes obsolete, there are all varieties of gradation, many of which 

 represent stages of growth in the most specialized forms. There are probably 

 some dextral forms, though such are apt to be referred to Cerithiopsis ; and 

 probably son^e of those referred to this group would, if we knew all the charac- 

 ters of the soft parts, operculum, etc., be naturally placed with Cerithiopsis, as 

 reversed species of that genus. 



I have felt that the differences of the soft parts, dentition, and operculum 

 were sufficient to authorize the use of the family name for this group, as has 

 been proposed by other naturalists. A great number of sectional names have 

 been proposed in this group. Most of them are without sufficient reason for 

 existence. We may conveniently recognize India Bayle (+ Ino Hinds, thrice 

 preoccupied), for the elongated species with flattened whorls, open anal aper- 

 ture, and sharp apex ; Sychar Hinds, for similar shells having a swollen nucleus 

 and more rounded whorls; Mastonia Hinds, for the short, swollen fusiform 

 species* with the same character of aperture; and Triforis s. s., for those in which 

 the anal sinus is closed, and all the foramina have a more or less tubular form, 

 when completely adult. These shells are so frequently decollate, rubbed, or 



