MELVILL : ON CONUS COROMAKDELICVS. 173 



the elevated conical apex, produced base representing the canal which 

 distinguishes the Pleurotomw, the condition of the outer lip, which 

 is not thickened within, and so strongly arched as to be almost semi- 

 circular in form, the deep wide sinus, which divides the posterior 

 extremity of the outer lip from the suture, and exactly resembles the 

 notch by which the Pseudvtomce (a section proposed by Bellardi) are 

 distinguished, and the elevated, reflected anterior margin of the 

 columellar lip, forming the right wall of the anterior canal." 



To sum up, I would venture to propose that the Swainsonian name 

 Conorbis be applied to C. Curonumdelmis, Smith, subgenerically, as an 

 isolated recent form, its place being between the subgenus Uermea, 

 Montfort (in which C. tendineus, Hwass., is one of its nearest allies), 

 and the section Genota, H. & A. Ad., oi Pleiirotoma 



I have mentioned that Mr. Townsend dredged these Cones alive ; 

 but the soft parts were not, unfortunately, retained. It is much to 

 be hoped that the next examples procured will be able to be 

 fully anatomically examined and reported on, as especially to be 

 compared with the animal of Genota. Indeed, in no assemblage 

 of Gastropoda are our attempts at classification and demarcation of 

 genera or subgenera so apt to become futile as in the wonderful 

 wealth of forms exhibited by thePleurotomidse, both recent and fossil. 

 "What is wanted for this family is a specialist to concentrate the whole 

 of his lifework upon it, and it alone. The number of new forms, 

 mostly abyssal, increases yearly, and very likely there exist further 

 links to bind the two groups we have been discussing, Conus and 

 Pleurotoma, together in more than one way. 



