73 



one an animal of a bright blue colour, the other of a rich coppery green ; 

 in the first of these, the proboscis appears to be furnished with a sort of 

 grappling rosette, analogous to the dentated extremity of the trunk in 

 3I'dra, the animal has not, however, the sluggish habits of that genus, by 

 reason of the light and portable structure of its shell. 



The Bolium shell is, for its size, the lightest of spiral univalves, ap- 

 proaching somewhat in form to that of Cassis, but fully distinguished by 

 its tenuity and want of varices, as well as by the absence of any recurvature 

 at the base. 



Species. 



1. Chinense, Desk. 5. jralea, Lam. 9. perdix, Lam. 



3. costatum, Besh. 6. maculatum, Lam. 10. pomum, Lam. 



3. fasciatum, Jjam. 7. melanostoma, Jay. 11. variegatum, Lam. 



4. fimbriatum, S020. 8. olearium, Lam. 



Figures. 



DoLiUM PEEDix. Plate E. Shell with animal, showing its expanded blue- 

 striped disk, with the auriculated structure in front, the conspicuous 

 head and tentacles, with the eyes on short peduncles at the base, the 

 respiratory siphon for conveying water to the branchial cavity, re- 

 clining back upon the shell, and the extended trunk with its dilated 

 rosette-like extremity. 



DonuM POMUM. Plate G. Shell with animal, showing its blue-striped 

 disk, the proboscis only partially exserted, tentacles, eyes, siphon, &c. 



DoLiuM OLEARIUM. Plate G. Shell with animal, showing its coppery 

 green disk, tentacles, eyes, siphon &c, the trunk being wholly with- 

 drawn. — All from the ' Voyage de I' Astrolabe '. 



DoLiUM FIMBRIATUM. Plate 5. Pig. 24. Shell, showing the aperture and 

 excavated columella. — From Mr. Cuming's collection. 



Genus 16. HARPA, Lamarck. 



Animal ; disc very large, elongated, semicircular in front, termi- 

 nating jjosteriorlg in a point ; head flattened, auriculated on 

 either side, tetitacles not very long, loith the eyes situated on 

 the outer side towards the base ; respiratory siphon very long. 



Shell ; ovate, ventricose, spire short, with the apex elevated and 

 acute; ichorls longitudinally varicose or ribbed; columella 

 synooth, highly enamelled ; aperture large. 



