MONOGRAPH OF THE SUBGENUS 



TROPHON. 



Generic Chakcter. — Testa canalifera, clavata, vel fusiformis, 

 varicibus longitudinalibus, numerosis, plerumque exfoliatis 

 vel inibricatis vel serratis, et frequenter liris aut sulcis spirali- 

 bus sculpta, canali aperto ; spira producta. Operculum 

 corneum, nucleo terrninali. — Most of the Tropbons might be 

 described as laminated Fusi or as Murices with open canals. 

 A few of the species, shewing the former tendency only in 

 early stages of growth or even not at all, are yet very closely 

 allied in other characters to those that shew it most fully. 

 T. Phllippianus, for instance, is a near ally of albolabratus, 

 and through it to Geversianus, which leads to cretaceus. T. 

 spiratus, a regularly laminated shell in its normal growth, 

 almost entirely loses that character in some of its variations. 

 The genus, however, as it stands adopted by conchologists 

 now is scarcely identical with that formed on the type of 

 T. muricatus, Mont., which is a simple Fusus. In this 

 work it is figured as a Fusus (f. 27, next monograph), but as 

 it will be naturally looked for here, it has been thought 

 best to give it a place (sp. 22) in this genus. 



Species. 



1. Geversianus, f. 7, 8, Pallas. — Testa subglobosa, pur- 

 pureo-fusca, varicibus albis, vel pallidis distantibus, late 

 exfoliatis superne angulatis, et sulcis spiralibus intermediis 

 ornata ; canali extus laminato, sub-angusto post labium in- 

 ternum umbilicato. — Of a globose form with broad laminated, 

 exfoliated varices, which are raised and angular at the top of 



