FUSUS. 



TESTA fusiformis, turrita, anfractibus plurimis, 

 plerumquerotundatisjcanali recto, plusminusve 

 elongate, apertura elliptica ; opereulo corneo, 

 infra acuminato, nucleo inferiore. 



Another of those genera which has properly been sepa- 

 rated from the Liiinean Murices, from which it is suffici* 

 ently distinct. The species of this Genus are for the most 

 part more or less regularly fusiform, with a turreted and 

 gradually acuminated, usually pointed^ though occasionally 

 mammillary spire, consisting of numerous, generally round- 

 ed volutions, which are frequently transversely ribbed and 

 spirally grooved on their outside ; aperture elliptical, 

 running into a more or less lengthened straight canal; 

 operculum horny, with its nucleus at its acuminated lower 

 end^ a thin horny, more or less rough or velvety epider^ 

 mis, usually covers the shells of this Genus in their natu- 

 ral state. 



!n this Genus, as in Pleurotoma, there are several 

 variations in form, which we will here endeavour to des- 

 cribe, and which we will illustrate in our plate: the first, 

 which may be called the typical form, as being that from 

 which it takes its name, has its spire and its canal of equal 

 length, its aperture elliptical, its last volution ventricose, 

 and the canal narrow, commencing by a sudden contrac- 

 tion at the base of the aperture; Fusus Colus, and Pusus 

 nicobaricus are examples of this form : next we may men- 

 tion those which approach in form to our Pyrulae, and 

 many of which Lamarck has united to his Pyrulae, these 

 have a shortened spire, a somewhat lengthened canal, and 

 the last volution is ventricose at its upper part, being some- 

 times tuberculated, and even having strong vaulted spines 

 around the upper part of the vplutions; for examples of 



