192 Dr. Turtoii on the Genus Lacuna. 



5. L. vincto, testa oblongO'Conica,fasciis quatuorfusois : anfractu 



majori ecarinato: sulco columnari dilatato. 



Shell oblong-couical, with four brown bands; the larger volution 

 not carinate at the base : the groove on the pillar dilated. 



Turbo vinctus. Montagu, 307. t. 20. f. 3. 



Shell much larger than the last, and distinguished by the 

 rounded base of the larger volution, and the more open 

 groove down the pillar. The bands are sometimes obliterated, 

 and rarely the four bands unite into two broader ones. 



6. L. canalis, testa conoidedj opacd, efasciatu: labio extcriori 



crasso. 



Shell conoid, opake, without bands ; the outer-lip thickened. 

 Turbo canalis, Montagu, 309. t. 12. f. U. 



A shorter shell than the last, and much thicker ; the outer lip 

 is also hard and thickened. 



7. L. crassior, iestd conoidea, ci'assa, apnea : anfractiibus tu- 



midis ; majori subcarinato : labio externo incrassato : sulco 

 columnari et umbilico obsoletis. 



Shell conoid, thick, opake ; volutions tumid, the larger one 

 slightly carinate at the base ; the outer lip thickened ; the 

 groove and umbilicus of the pillar obsolete. 



Turbo crassiorj Montagu, p. 309. t. 20. f. 1. 



This seems to be the link connecting the two families of Turbo 

 and Lacuna ; but evidently belonging to the latter, as the groove 

 and umbilicus arc sometimes faintly visible. When fresh it is 

 covered with a pale-brown, much wrinkled skin, under which it is 

 of a polished, opake, milk-white colour. The very tumid volu- 

 tions, and the su})carinate base of the larger one, distinguish it 

 from the Lacuna canalis. 



