486 CONID^. 



Mangelia pusilla. Reeve, Conch. Icon. vol. iii. M;nig. pi. 7, f. TiO. 



„ bulteata. Reeve, Conch. Icon. vol. iii. Mang. pi. 7, f. 57, from type. 



It is impossible to precisely ascertain what Pennant 

 meant by his Murex costatus, so bald is his description, so 

 imperfect his delineation : the present shell, however, is its 

 traditional representative. Donovan first clearly defined 

 the species, for Da Costa's figure is very uncertain, but we 

 doubt not, from the personal intimacy of the two authors, 

 that their species are identical. We are compelled to 

 annex the P. coarctata as a variety, since in a long suite of 

 examples, the peculiar differences merge into each other. 

 As the latter form has been less frequently described, we 

 shall, contrary to our usual habit, give a more detailed 

 account of it, and then indicate the differences in the 

 typical specimens of costata. 



The shell alluded to is strong, opaque, of little lustre, 

 and of a turreted-fusiform shape ; but the form varies, as 

 the spire is sometimes much more elongated than ordinary. 

 Numerous tawny lines, that are sometimes a little inter- 

 ruptedly spiral, sometimes form an irregular net-work, 

 adorn the whitish ground of its exterior, besides which a 

 broader interrupted fillet of brown or fulvous, often winds 

 below the sutural line, and a similarly-coloured blotch, 

 like the commencement of another band, frequently makes 

 its appearance, behind the lip, near the middle of the body. 

 Seven or eight strong and very prominent slightly flexuous 

 rather distant abruptly elevated ribs traverse the shell 

 lengthways; besides which most minute and densely-disposed 

 spiral striai are disclosed by a magnifying-glass of ordinary 

 power ; the intervals of the ribs are concave. Although 

 the eight and a half moderately high and but little rounded 

 whorls that compose the shell are only divided by a fine 

 suture, they are well defined by the greater elevation of 



