HARPA.— Plate II. 



Buccinum harpa, var. e, Bruguiere. 

 Buccinum costatum, Linnaeus. 

 Lyra Davidis, Martini. 

 Hab. Mauritius (found in sand, in rocky places in deep 

 water) ; Cuming. 



This very beautiful and highly valued shell has been 

 considered by some authors to be merely a many-ribbed 

 variety of the Harpa ventricosa, on account of the uncer- 

 tain number and proximity of the ribs in that species ; 

 it requires however, in my opinion, no very great power 

 of discrimination to remark one or two important cha- 





racters in the Harpa imperialis which are decidedly pe- 

 culiar to that species. The ribs, without regard to 

 number, differ essentially in being rounded ; the inter- 

 stices between them are deeply striated, and never ex- 

 hibit the least indication of that bold festoon-painting 

 which forms so prominent a feature in the Harpa ventri- 

 cosa ; and again, there is a strong peculiarity in the 

 columella and interior of the shell being lined with an 

 enamel of bright orange. Other differences might be 

 particularized, but these are fully sufficient to establish 

 the accuracy of Lamarck's arrangement. 



