EUROPEAN SPECIES OF VERTIGO. 161 



42. VERTIGO PUSILLA Miiller. PL 16, figs. 1, 2, 3. 



Shell subfusiform, with, somewhat of a quadrangular out- 

 line, thin and semitransparent, very glossy, horn-color, with 

 a faint tinge of yellow, very slightly and remotely striate in 

 the line of growth; periphery rounded, with a tendency to 

 angularity ; epidermis thin ; whorls 4% or 5, very convex and 

 cylindrical, gradually increasing in size, the penultimate whorl 

 as broad as the last, which occupies about two-fifths of the 

 shell; spire shortish, but rather tapering, and blunt at the 

 point ; suture very deep ; mouth semioval, contracted or sinu- 

 ous in the middle of the outer edge; teeth six or seven, viz. 

 two on the pillar [parietal wall], two on the pillar lip (the 

 inner one of which is always larger, and the outside one 

 tubercular and placed in the angle where the outer lip 

 joins), and two or three within the outer lip (the third, when 

 it is present, placed near the pillar lip and being a mere 

 tubercle:) outer lip rather thick and slightly reflected, 

 strengthened by a strong rib both outside and inside, which 

 is situate near the opening of the mouth and is yellowish- 

 white ; outer edge rather abruptly inflected ; inner lip slightly 

 thickened in full grown specimens; umbilicus small and 

 narrow, contracted by a rather sharp and gibbous crest or 

 ridge at the base of the shell. L. 0.07. B. 0.045 inch 

 (Jeffreys). 



Europe; Caucasus; Asia Minor. 



Vertigo pusilla MULLER, Vermium terr. et fluv. Hist., ii, 

 1774, p. 124. A. MULLER, Wiegm. Archiv f. Naturg. 1838, i, 

 p. 211, pi. 4, f. 5. ROSSMAESSLER, Iconogr. ii, pt. 10, p. 29, 

 pi. 49, f. 649.--JEFFREYS, Brit. Conch, i, p. 263. MOQUIN- 

 TANDON, Moll. France ii, p. 409, pi. 29, f . 12-14. Pupa pusilla 

 (Mull.) PFEIFFER, Monographia ii, p. 364; iii, 560; iv, 686; vi, 

 336 ; viii, 404. KUSTER, Conchyl. Cab. p. 129, pi. 16, f . 38-40. 

 WESTERLUND, Fauna iii, 1887, p. 141 ; Acta Soc. pro fauna 

 et flora Fennica xiii, no. 7, p. 70 (dist. in Norway, Sweden, 

 Finland). Helix vertigo GMELIN, Syst. Nat. (13), p. 3664. 

 Pupa vertigo DRAP., Hist. Moll. France, p. 61, pi. 3, f . 34, 35. 

 Vertigo Keterostropha Leach, TURTON, Manual, 1831, p. 105. 

 LEACH, Synopsis Moll. G. B. 1852, p. 94. 



