36 BOOK OF SPECIES. 
ACHATINA. TERRESTRIAL. 
Ovate or oblong; aperture entire, elongated; lip 
acute, never reflected ; columella smooth ; the 
base truncated. 
* Last whorl ventricose, and not depressed. 
A. PERDIXx. Very large, ovate-oblong, ven- 
tricose, decussated, white; apex rose-colour, 
marked with longitudinal dark-chestnut flames ; 
columella of a violet purple; lip white within ; 
sutures slightly crenulated. 5. W. 18. 53. 
A. ZEBRA. Very large, ovate-oblong, ventri- 
cose, obsoletely decussated, and marked with 
crowded, longitudinal, undulated, red and brown 
lines or streaks; lip white within; sutures and 
size as preceding. W. 18. 52. 
A. PURPUREA. Ovate, ventricose, cinerous, 
covered with a yellow epidermis ; apex pinkish ; 
mouth purple, both lips margined with brown ; 
spire obtuse; sutures crenulated. 4. W. 18. 
5A. 
A. VEXILLUM. Ovate-conic, smoothish, most 
minutely striated, variously coloured, banded, and 
spotted ; whorls eight, rather convex; columella 
pink, by age black. 3. W. 18. 46. 
A. VIRGINEA. Ovate-conic, smooth, white, 
elegantly girded by black and red lines; whorls 
convex ; columella rose-colour ; lip purplish ash- 
