"220 ENGINA, NASSARTA. 



great individual variation. I \niite with this species P. textilinus, 

 Miirch. Nassa unicincta, Say (fig. 612), is an unidentified species 

 which may possiblj^ equal Gnadeloupensis : if so, it will have 

 ))rioritv. 



Doubtful and Undetermined Species. 



Ph. sculptilis, Ph. varicosus, A. Ad. Mentioned in H. and A. 

 Adams' Genera, but not described. 



Ph. cancellare, Menke, Ph. titjmalk. Phil. Marquesas Is. 

 Ph. fusoides, C. B. Ad. Panama. 



A single specimen described as a Triton^ having varices upon 

 the whorls. P. P. Carpenter, who has examined it, says that it 

 is not a Triton however, that the aperture has an anterior sinus 

 of the lip, and that it may be an Euthria. The lip sinus and 

 other characters, however, agree well enough with Phos. 



Ph. BiPLiCATUS, Carpenter. Panama. 



Not figured ; described from a single specimen. The diagnosis 

 fairl}- applies to Ph. Veraguensis, Hinds. 



Genus ENGINA, Gray. 



A group of Columbelloid shells, nodulously, longitudinally 

 ribbed. The dentition of one species, E. mendicaria, has been 

 published (PI. 27, fig.36), and exhibits the characteristic features 

 of the PliotinjB. There must always be some doubt as to identifi- 

 cation of species in a case where, like the present one, a single 

 character antagonizes all the others; and, on consideration, I 

 prefer to continue to include Engiiia among the Columbellida' 

 until the weight of evidence shall be more decisively against it, 

 tlian it is at present. Even if no mistake lias been made, and 

 the liugual examined was that of E. mendicaria^ it by no 

 meaus follows that tlu; otliei' species possess similar armature. 

 So decidedly is the shell Columbelloid that to separate the genus 

 on account of the dentition of a single si)ecies would he, I think, 

 uupliilosopliicnl and undesiral)le. 



(ifiius NASSARIA (Link), H. .1 A. Adams. 



Animal with the tentacles connate at the base; with the eyes 

 near tiieij- distal ends; foot anti^rioily produced, ending behind 

 in a simple tail witliout lllainent. 



