Zoological Illustrations/VolIII-Pl181

Zoological Illustrations
William Swainson
Vol III. Pl. 181. Voluta Pusio. Dwarf Volute.
1314683Zoological Illustrations — Vol III. Pl. 181. Voluta Pusio. Dwarf Volute.William Swainson

Lamarck's recent account of this genus, in the last volume of his Animaux, contains but two species in addition to those long ago described by him in the Annales du Mus.; thus omitting many of those new Volutes which of late years have been discovered. On the other hand, this naturalist has created five species from the varieties of V. musica Lin. resting their characters on colour, bands, and the number of the lesser or spurious plaits on the pillar. It requires no argument to prove that these principles of distinction are the most uncertain he could have chosen; scarcely two specimens of V. musica being found alike. These supposed species must, therefore, again merge into one.

VOLUTA Pusio,

Dwarf Volute.

Generic Character.—See Pl. 161.


Specific Character.

V. testâ ovato-obtusâ, flavescente, fasciis pallidis, maculis fulvis interstinctis cinctâ; anfractu basali obtusè nodoso; spirâ brevissimâ, acutâ; columellâ incrassatâ, multiplicatâ.
Shell ovate-obtuse, yellowish, with pale bands and fulvous spots; body whorl crowned by compressed obtuse nodules; spire very short, acute; pillar thickened with many plaits.
Voluta Pusio. Swainson, in Tilloch's Ph. Journal, vol. 61. p. 378.

The shell before us has more important characters; the body whorl is quite smooth, but crowned by compressed truncated nodules; the spire remarkably short, and the tip acute; in other respects it approaches to V. virescens Sol. (Polyzonalis Lam.) and to V. fulva Lam. I have neither of these shells at present before me; but if Lamarck's description of them, and the figures which he has cited, be correct, I have no doubt they are but one species; V. polyzonalis being the smooth, and V. fulva being the nodulous variety of Solander's V. virescens. In fact, Lamarck says both shells are transversely striated.

V. pusio is a shell of the greatest rarity, and is described from a specimen in the collection of my friend Mr. Broderip. Its form is perfect, but its colours are somewhat faded.