Fusus. 415 



FUSUS. Lamarck. 



Shell fusiform, usually stroug, solid, and often invested 

 with an epidermis, spire produced, body-whorl ventricose, 

 surface ribbed, sulcated, spirally striated, or rarely nearly 

 smooth ; aperture ovate, produced below into a more or 

 less elongated canal ; pillar lip smooth. Operculum cor- 

 neous, unguicular, its nucleus terminal. 



Animal ample, its head flanked by rather thick subulate 

 tentacula, bearing the eyes on bulgings on their outsides 

 not very far above their thickened bases, which internally 

 are separated from each other by a capital lobe : proboscis 

 long, tongue armed with transverse rows of teeth, each 

 row composed of a quadrate axile loop, flanked on each side 

 by a hamate or scythe-shaped lateral ; mantle even-edged, 

 siphon not very much produced beyond the canal ; branchial 

 plumes two, unequal ; male organ large, falcate, flattened ; 

 foot large, oval, sub-truncated in front, obtuse behind, 

 bearing the operculum on a very short rounded lobe. 

 Nidus of one or more corneous capsules. 



The Fusi which occur in the British seas belong to that 

 section npon which Mr. Gray has revived the genus 

 Chrysodomus of Swainson, and which along with Buccinum 

 undatum and its allies, constituted the old genus Tritonium 

 of 0. F. Miiller ; a name that might be used, as several 

 naturalists have proposed of late years, with advantage, 

 were it not that it has unfortunately been adopted into 

 general use for a very distinct assemblage of Murlcid^. 

 Mr. Searles Wood includes the Fusi in Trophon^ and 

 Agassiz has proposed to call them Atractus. 



The sectional group is mainly composed of species from 

 cold or temperate regions. They inhabit all depths of 

 water between the laminarian zone, and one hundred or 



