HELIX. 233 



very depressed specimens of Helix ligcra, but none 

 approaching this. It may, however, be subject to still 

 further reductions in the height of the spire, until it 

 reaches the depression of the present shell. If it should 

 be the same, it will exhibit very extraordinary variations 

 in this respect, from a high conical to a planulate form. 

 It resembles Helix snppressa externally, in every thing 

 except in size and in being less coarsely striate. 



64. HELIX LUCIDA. 



PLATE XXII. a. FIGURE 2. 



H. testa orbiculato-depressa, late umbilicata, nitida, pel- 

 lucida, fulvo-fusca ; anfractibus quinque convexiusculis, 

 ultimo tereti, circa umbilicum excavate ; apertura lunato- 

 circular!, labro acuto, simplici, margine basali arcuato. 



SYNONYMS AND REFERENCES. 



Helix nitida, MULLER. Verm. II. 32, No. 234. 



also of Lamarck, Bock, PfeifTer, &c. 

 Helix luc iJa, DRAP. 103, pi. 8, f. 11, 12. 



also of Rossmassler, J. E. Gray, &c. 



DESCRIPTION. 



ANIMAL not described. 



'"is U, u. \k,.<O 



SHELL orbicular, depressed, moderately convex above 

 and concave below, thin, shining, brownish horn-color, 

 with delicate striae of growth. Whorls five or more, con- 

 vex, separated by a deeply impressed suture, the outer 

 one disproportionately large, somewhat declining as it 



VOL. ii. 30 



