PUNCTURELLA. 47 3 



PUNCTURELLA, Lowe. 



Shell conical, with an elevated slightly recurved 

 obliquely subspiral entire vertex, turned towards the 

 posterior end ; aperture expanded, oval ; surface with 

 radiating ribs ; margin entire ; a linear perforation in the 

 upper part of the shell, between the vertex and frontal 

 margin, ill the line of an elevated rib. Interior with a 

 linear groove corresponding to the perforation and frontal 

 rib, vaulted over in its upper part by a shelly plate. 

 Muscular impression crescentic, with slightly-incurved 

 extremities, interrupted in the region of the head. 



Animal with a short muzzle-shaped head, bearing two 

 subulate tentacles, which have the eyes placed on promi- 

 nent bulgings, or rudimentary pedicles, at their external 

 bases ; a range of cirrhi interrupted behind on each side ; 

 mantle simple-edged ; anal siphon very prominent, forming 

 a truncated membranous canal projecting from the suba- 

 pical perforation ; branchial plumes two. 



The curious shell from which this genus is founded, 

 rejoices in three if not four appellations, devoted entirely to 

 itself: we adopt that which was given it with a full under- 

 standing of its claims to generic distinction by a naturalist 

 whose every labour among the Mollusca is so excellent, 

 that we could wish his published researches were much 

 more numerous than they are. The synonyms, Cemoria 

 and Sypiio, cited in nomenclature catalogues as of prior date, 

 were neither of them published with generic diagnoses, and, 

 moreover, seem to have been suggested to their authors by 

 the fry of the Fissurella Graca. Loven refers the following 

 shell to the Rimula of Defrance (founded for certain fossils, 

 VOL. n. 3 P 



