VERTIGO. 441 



Vertigo milium. 



Fig. 118. 



Shell sub-oval, Tvrinklecl, light chestnut colored; whorls four; suture moder- 

 ate; aperture heart-shaped, armed with six teeth; umbilicus I'ree. 



Pupa milium, Gould, Best. Joiirn. iii. 402, pi. 3, fig. 23 (1840) ; iv. 359 (1843) ; Inv. 

 187, fig-. 181 (1841).— De Kay, N. Y. Moll. 48, pi. 4, fig. 44 (1843). — Adams, Ver- 

 mont .Moll. 153 (1842). — Pfeiffer, :\Ioii. Hel. Viv. ii. 362. — Binney, Terr. Moll, 

 ii. 337, pi. "1, fig. 1. — KiJSTER, in Chemn. 2d ed. 119, pi. 15, figs. 39-42. 



Vertiffo milium, W. G. BixN. T. M. iv. 148. —Morse, Am. Nat. i. 669, figs. 65, 66 (1868). 



Shell minute, of a nearly oval form, color a light chestnut ; whorls 

 four, or somewhat more, obviously wrinkled, 

 rather convex, arranged so as to form a bluntly 

 rounded apex ; suture deep ; aperture half the 

 width of the last whorl, heart-shajjed, the apex 

 being its right upper angle ; the transverse mar- 

 gin is nearly direct, the outer margin is scal- 

 loped by an indentation of the lip ; the remain- 

 der of the margin is regularly rounded ; lip 

 white, slightly everted ; throat with six teeth, two of which are on 

 tlie transverse lip, equidistant ; one witli a tubercle at its base, on 

 the middle of the left lip, and nearly at right angles Avith the for- 

 mer is the largest ; a fourth is on the indenture of the outer lip, 

 directed between the two on the transverse lip ; and two smaller 

 ones, more retired within the shell, are equidistant between the two 

 last mentioned ; umbilicus large and deep. Length, less than one 

 thirtieth of an inch ; breadth, one fortieth of an inch. 



This shell I first found in November, 1839, at Oak Island, Chel- 

 sea, after a warm rain. Professor Adams has found it in Vermont. 

 It was crawling on the damp leaves, in company with Cionella sub- 

 cylindrica. From New England to Texas. 



Not finding any description answering to it, I have proposed a 

 name. It is even more minute than Carijchium exifrnum^ and is not 

 readily detected. In size and outline it resembles P. veriig-o, Drap., 

 V. pusilla of other authors ; but that shell is reversed, and has a 

 different armature. The teeth are all distinct, long, compressed, and 

 very sharp. 



I have laljored to make this out to be the P. ovata of Say ; but 

 on the whole I think the discrepancies are too important to be rec- 

 onciled. That shell is described as larger, with a semi-oval aper- 

 ture, and M'ith seven teeth, differently arranged from those of our. 

 shell. 



