FAMILY IANTHINIDJB. 



Shell thin, fragile, turbinated ; whitish ov purplish; aperture 



ov:il or sublet ra'j;onal. 1 he columella :i little twislrd. lip simple, 

 curved. No opereiilum. 



Animal pelage, sustained by a vesicular body called the tl 

 nnd to which the eir^s ' re attached. The ilo:it is composed of 

 a mass of vesicles filled with air, the walls resist in<_r. subca rtila- 

 ginoilS, supported by a narrow pedmiele. formed hy and adhering 

 to the foot. Sexes separate, no copuhitory or^an. Ivostruin 

 pi-ohoscidifonn ; no jaws ; radula, composed of a ^reat number 

 of elongated teeth, no central tooth. Carnivorous. es a 



purple fluid, which is ejected from the branchial cavity, when 

 irritated. 



Genus IANTIIINA, Lam., 1709. 



Uead larLjv, nuizzlc-shaped, e^yes not visible or sessile, tentacles 

 forked so that each appears like a pair, foot rather short, the 

 epipodial lobe somewhat elongated and ciliated, branchial 

 plumes two, unequal. 



The float is found in both sexes, and whilst in the female the 

 eggs are usually attached to the lower surface thereof, the 

 animal in some species is viviparous; embryos taken from 

 the uterus are operculated, the head has a ciliated velum, the 

 eye- are lar^e and well ))i^mented. 



Shell imperforate, without epidermis, fragile, trochiform or 

 turbinilbrm, nucleus small, sty li form, oblique, spin' li^lit pur- 

 plish white, base deeper purple; whorls fe\v, convex, with striae 

 of growth, angular or uathered at the periphery; outer lip with 

 a sinus in the middle, columella thin, twisted. 



About 30 nominal species have been described, from the 

 Atlantic and Pacific Oceans; 1 reduce them to three species, 

 with a few variet ie->. 



A is found in the Pliocene of Italy. 



Reeve monographed lanthina in 1858, including -2^ species, a 

 portion of which he first described, and M-'irch, in the Journal 



(33) 



