215 



volutions. Another immature specimen (fig. 2c), whose apex is not 

 quite perfect, and which measures twenty-nine mm. (or an inch and a 

 quarter) in length and eight mm. at the larger end, has eleven volutions 

 presei-ved. The entire number of volutions was probably about twenty. 

 This species belongs to the sub-genus Nerinella of Sharpe. 



Cerithium Skideqatense. (N. 8p.) 

 I'late 27, figs. " and 3a. 



Shell small, not much exceeding half an inch in length, pupiforra, 

 turreted but not much elongated, the length being about twice the 

 greatest breadth : whorls six or seven, the earlier ones obliquely com- 

 pressed, the later ones more cylindrical : spire not much longer than 

 the last whorl preserved, and possibly not any longer than the body 

 whorl, which is more or less broken in all the specimens collected : 

 suture angularly but not vejy deeply impressed. Surface marked by 

 rows of beaded or tubei-culated spiral raised lines. On the two last 

 volutions but one there are four rows of nearly equidistant, pi*ominent 

 and regulai'ly rounded tubercles. On the upper or posterior half of 

 the last volution preserved there are also four rows of bead-like 

 tubercles, and on the lower or anterior half of the same volution thej*e 

 are three or foui- spiral raised lines, the uppermost of which is 

 indistinctly tuberculated. 



Length of the most perfect specimen (in which part of the body 

 whorl is broken oif,) eight millimetres; breadth rather more than 

 thi'ce and a-half mm. ; length of the last whorl (which is imperfect) 

 nearly foui- mm. 



East end of Maud Island, ojjposite Leading Island : five or six well 

 preserved but imperfect specimens. 



Vanikoro pulchella. (Nom. pi-ov.) 

 Plate 27, figs. 4 and 4a. 



Possiblj' a variety of Lt/owma PovkIM, White. 



Com.}]. Neritina ? f Poiodli, White. —1876. Powell's Eeport on a Geological 



Survey of the Uinta. Mountains, p. 110. 

 " Lyomma Fovdli, White. — 1880. U. S. Geol. Survey, Contributions 



. to Paleontology, Nos. 2-8, p. 153, pi. 30, 

 figs. 6, 6a, 6b, 6c, and 6d. 



Shell obliquely subovate, its length and breadth being nearly equal : 



