120 



var. a Cerithium Bawsoni Krebs mss. 



T. tenuissinia, liris obsoletissimis vel omnino evanes- 

 centibus; anfr. convexi, sutura profunda; unicolor casta- 

 nea, albo fasciata vel omnino alba. Labro intus lasvi- 

 gatus. Tritonium Humplireysianum quoad formam et 

 sculpturam. 



Long. 10 mm.; lat. 5 mm.; spm. majora datur. 



Cerithium luctuosum Mke. Sow. Thes. f. 147. sed 

 labro intus crenulato. 



Cerithium gallopaginis Sow. Thes. f. 155. 156 quoad 

 formam. 



Hab. Barbados? Rawson (Krebs.) 



sect. 3. 

 285. Cerithium aberrans C. B. Adams. 



„Sh. long ovate conic: Avhite: strongly sculptured 

 with 3 or 4 spiral ridges, which are decussated, wdth 

 nodulous intersections, by transverse ridges, of which 

 there are about 16 on each whorl; anteriorly the trans- 

 verse ridges are obsolete, and 3 or 4 additional spiral 

 ridges are nodiferous; apex acute: spire with the right 

 aide nearly rectilinear and the left quite curvilinear, the 

 axis being curved: whorls 7, nearly planulate, with a 

 subcanaliculate suture; last whorl rather large: aperture 

 rather small, deeply notched anteriorly ; labrum rather 

 thiek and well excurved. This species connects the 

 genus with those Cerithia, in which the canal is reduced 

 to a notch." Ad. 



Long, spirae 0,, poU. ; long. tot. 0,^^^ poU.; lat. 0,^^ poll. 



Rissoa aberrans Ad. Contr. p. 113. 

 Hab. Jamaica (Ad.) St. Thomas (Schölten, Riise.) 



Vera Cruz? (Liebm.) 



Labro s»pe intus 3-dentato. 



286. Cerithium alabastrum Mörch. 



T. solidula, alba, elongato-ovata, liris spiralibus con- 

 fertis sequalibus, 6 in anfr. spirse, interstitiis linea inter- 

 calente; costis linearibus confertis, undulatis, in anfr. 



