CERITHIUM. 



C. INTERRUPTUM, Menke. PL 27, figs. 24, 25. 



Form of the preceding species but more finely irregularly 

 grooved, with' intervening ridges ; whitish, marbled or closely 

 spitally lined with chocolate. Lerjgth, 12-15 mill. 



Cape St. Lucas, L. Cal. to Panama; Gallapagos Is. 



C. sculptum, Sowb. (fig. 24), is a synonym. 



Var. GALLAPAGINIS, A. Ad. Fig. 25. 



The spiral grooves crossed by slight, close longitudinal riblets, 

 forming a somewhat beaded surface. 



Guacomayo ; Gallapagos. 



C. NITIDUM, Hombr. et Jacq. PL 27, fig. 31 (lower). 



Vitreous white, channeled, with a line of tubercles next below 

 the suture, which are sometimes yellowish. Length, 1 in. 



Mangareva Is. 



C. B^TICUM, Pease. PL 27, fig. 26. 



Thin, with alternate shallow grooves and ridges, the former yel- 

 lowish, the latter chestnut colored ; these colors also appear in the 

 aperture ; the upper whorls are obscurely ribbed and nodulous. 



Length, 6 mill. 



Sandwich Is. 



C. LINEATUM, Dunker. PL 27, figs. 27, 28. 



Granulated by revolving ribs and intermediate grooves, and less 

 prominent longitudinal sculpture ; white, with two close, interrupted 

 chestnut lines on the middle of each whorl. Length, 5 mill. 



Viti Is. 



C. MONACHUS, Crosse and Fischer. PL 27, fig. 21. 



Rather thin, subtranslucent, reddish yellow, covered with minute 

 chestnut markings ; whorls 10, rounded, obtusely carinated, carina 

 forming an articulated band, last whorl with two obtuse carinse, 

 spirally striated, occasionally varicose. Length, 18 mill. 



Port Adelaide, Australia. 



The authors consider the species a Cerithidea. 



C. LACTEUM, Kiener. PL 27, figs. 29, 30, 33. 



Spirally grooved, crenulated near the suture, or sometimes min- 

 utely granular ; white, or yellowish white, sometimes with a row of 

 subsutural chestnut spots, sometimes with obscure zigzag chestnut 

 strigations. Length, 15 mill. 



Sandwich and Viti Islands. 



