VERTIGO. 
173 
Inhab. marshy situations, on Isolepis fluctuans, 
(^Gray^ 1817.) 
Animal grey-black and shining ; upper tentacles 
short, inflated at the base, lower dot-like ; front of 
head proboscis-like. 
Shell smaller than the last, of a deep chestnut- 
brown colour, with the margin of the aperture 
whitish ; teeth three above and three below, and one 
on each side, and often a ninth tubercular tooth. 
It may easily be distinguished by the three very 
discernible white teeth of unequal size within the 
upper and truncated part of the aperture, whereas 
there is only a single central one apparently visible 
in the same position in V, pygmcEa^ and two in V. 
suhstriata. The mouth varies with from six to nine 
teeth. 
b. Shell cylindrical fusiform^ sinistra! ; mouth mar- 
gined externally. (Vertigo Muller. Vertilla 
Moq. Tand.^ 
80 . 7. Vertigo pusilla. Wry-necked Whorl Shell. 
— Shell ventricose, attenuated, bald, rather 
shining, very brittle, pale brown ; whorls five ; 
mouth subquadrate, rounded beneath; plaits 
six or seven, white, two or three on the column, 
and four on the lips ; peristome thin ; umbilicus 
rather narrow, (t. 7. f. 86.) 
Vertigo pusilla. Muller ^ Verm, ii. 124. ; Alder ^ Mag. ZooL 
and Bot. ii. 112. ; Jeffreys^ Linn. Trans, xvi. 361. — Jaminia 
heterostropha. Risso, iv. p. 91. — Vertigo heterostropha. 
Turton^ Man. 105. f. 88. ; Leach.^ Moll. Syn. 94. — Pupa 
Vertigo. Drap. Tahl. 57., Hist. Moll. p. 61. t. 3. f. 34, 35. 
— Pupa pusilla. L. Pfeiffer, Mon. H. ii. 364. ; Forhes and 
Hanley, B. M. iv. 111. t. 130. f. 8. — Helix Vertigo. Gmel. 
S. N. 3664. — Turbo Vertigo, var. Mont. T. B, 365. 
