Zoological Illustrations Series II/Plate 9



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 "Animaux sans Vetebres" of the celebrated Lamarck was published in Paris; in which is described several species, figured in our 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 Rev. L. Guilding, whose accuracy of observation can only be equalled by his indefatigable zeal, has established the distinction between the horny and shelly operculated Ampullariæ, 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 operculum, remains with the true Ampullariæ.

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 Manchester Museum, and in our own.