i 



ACHATINA, 



(but in some species it has an undated mai'gin, and those 

 species are the Polyphemi of Montfort) ; the inner lip does 

 not spread far over the lower part of the last volution, 

 and the columella is smooth^ free from teeth or folds, 

 and truncated at its lower extremity; this latter joined 

 to the thin edge of the outer lip^ forms the essential 

 character of the Genus and existing in all that we here 

 combine in it, serves also to distinguish it from others, 

 particularly from Bulimus which resembles it in general 

 form. 



The Achatinae are the largest of all known land shells ^ 

 many of them^ such as A. Zebra, are naturally covered , 

 with a strong epidermis : others on the contrary, the A, 

 virginea for instance, appear to be destitute of it ; some 

 are constantly reverse shells, such are the large dark 

 brown African Achatina, which we believe Lamarck calls 

 A. bicarinata, and the A. Columna, Helix Columna, Linn,; 

 this last is perhaps one of the most singular of land shells^ 

 its columella forming a winding pillar, visible within to 

 the very summit of the spire; it is the Tiger Lendix of 

 English Collectors, and the Colonne torse of the French. 



The greater number of Achatinae are African shells; 

 some are West Indian, and a very few European; among 

 the latter we can only lay claim to one as decidedly ^ 

 native of this country, the Achatina Acicnla of Lam., 

 Buccinum terrestre of some English Authors. We hesitate 

 to consider as decidedly British, a little shell that we 

 believe belongs to this Genus, found by that acute and 

 zealous naturalist, Mr. Miller, in pine-beds, at Bristol. 



In our plate we have represented three shells belong- 

 ing to the three divisions of the Genus : — 



Fig. 1 . Is one of the ordinary character, whose aperture is about half the 

 length of the shell, it is the A. purpurea of Lam. Bulla purpurea, Dillw. 



2. Achatina virginea, whose aperture is scarcely longer than it is wide, 

 and not nearly equal in length to the spire. 



3. A. leucozoniaSf Lam. Valuta leucozonias, rHllw.; one of the Poly- 

 phemi of Montfort, whose outer lip is undated, and the aperture proportionably 

 longer than usual. 



