AMPULLARIA arinata. 
Carinated Apple-snail. 
EEE 
Family Ampullaridee.—Guild. 
GENERIC CHARACTER. 
PacHysToMA. Shell ventricose; margin of the lip thick, generally 
grooved ; operculum testaceous. Zool. Journ. 12. p. 536. 
SpeciIFIC CHARACTER. 
Shell olive, ventricose, without bands; whorls carinated near the 
suture. 
eer 
In the first Series of our Illustrations, we endeavoured to 
lessen the confusion which, at that time, prevailed among 
the species of Ampullaria, figuring and naming such as 
appeared to us truly distinct. During the course of our 
labours, the sixth part of the “Animanzx sans Vetebres” 
of the celebrated Lamarck was published in Paris ; in which 
is described several species, figured in vur volumes under 
other names. A want of mutual communication between 
authors writing at the same time, and on the same subject, 
has naturally caused confusion in nomenclature ; which, at 
an early period, we intend to elucidate. 
Our friend the Rey. L. Guilding, whose accuracy of 
observation can only be equalled by his indefatigable zeal, 
has established the distinction between the horny and shelly 
operculated Ampullarizx, on anatomical principles. The 
present species (which was engraved before his valuable 
memoir was published) must consequently be placed in his 
genus Pachystoma ; while the carinata of Lamarck, from 
having a horny cperculum, remains with the true Am- 
pullarie. 
We know not the precise locality of our species; but 
conjecture it may be from some of the rivers of India.— 
Specimens, in different stages of growth, are in the Man- 
chester Museum, and in our own. 
Ampullaria PI. 1. 
