UNIVALVES. 



PLATE XXXVII. 



Genus. TEREBELLUM. 



Character. Shell spiral, widening towards the base ; the apex acute ; the opening 

 of the mouth longitudinal, narrowed at the upper end, the base emarginated with- 

 out teeth ; the columella truncated ; no beak. 



Species. 



•No. 1. Terebellum lineatum. Shell of a pale yellow colour; the mouth of a 

 dark brown, oblique lines of red running in a slanting direction across the 

 body, two and two, the lowest end of the mouth appearing as if cut off sud- 

 denly. 



No. 2. Terebellum spirale. Shell of an olive yellow ; the mouth of a dark blue ; 

 the spire marked regularly with oval brown spots, and lines of brown invest- 

 ing the body and cheek transversely. This shell, as well as the former, is 

 supposed to be rare. It is brought from the Eastern Ocean. 



Genus. CYMBIUM. 

 Character. Shell, the spire involved or covered over with the body of the shell, 



leaving only a small rounded top or apex ; the mouth longitudinal, arcuated, cut 



open at the bottom by a wide channel, dividing it from the columella, which is 



fluted, with undulated and painted divisions. 



Species. 



No. 3. Cymbium spinosum. Shell of a bright amber colour ; the spire almost con- 

 cealed, and surrounded with spines ; the mouth spreading out, of a pale pink 

 colour. This elegant shell, so captivating by its form and colours, is a na- 

 tive of Ceylon and Madagascar. 



No. 4. Cymbium bandatum. Shell of a lively amber colour, richly banded with 

 transverse red shades ; the mouth being of a pale red ; the spines of the 

 apex short and rounded. This species is rather uncommon, and is brought 

 from the South Seas. 



No. 5. Cymbium purpureum. Shell purple, spotted with brown spots, placed in 

 bands transversely ; the mouth white ; the apex small, and enclosed. 



REMARKS. 



There exists in the genus Terebellum and Cymbium a distant resemblance in the form and 

 character of several parts. The open channel and want of beak form a characteristic mark 

 of the Terebellum. The spire parti y hid and covered up by the foldings of the cheek in the 

 Cymbium, distinguishes it clearly from the Voluta and other shells, with which it has hither- 

 to been too much confounded ; the bands are also very distinguishable on the base, being 

 of a different colour from the rest of the shell, particularly the first, which is generally 

 purple. There is also much difference in the form of the apex, or summit of the spire, being 

 in some species spinous, in others quite involved by the folds of the cheek, and nothing left 

 but the small round tubercle at the top, and that barely visible. It takes its name from its 

 general resemblance to a flask, or drinking cup. 



