GASTEROPODA. 65 
into about four vertical undulations, so as to touch the plane on which 
it moves at as many points ; and these undulations pass from the tail 
towards the head as the animal moves, as in the motion of the caterpil- 
lar or millipede. 
SHELL sub-globose, strong, coarse, obtusely keeled at the periphery, 
of a pale chestnut-brown, which is here and there diluted so as to form 
large, irregularly disposed clouds, and sometimes bands, the shades 
blending with each other; the region of the apex is generally pale, 
and that of the umbilicus dusky. Whorls six, well rounded, with 
coarse, irregular strie of growth, the suture deeply impressed. The 
aperture is large, rounded, its diameters about equal; throat livid, 
becoming darker near the lip; peristome slightly reflexed, whitish, 
the basal portion nearly horizontal, and the extremities widely sepa- 
rated, columella rapidly widening, so as to leave a mere chink of the 
umbilicus uncovered; a very thin coating of enamel unites the two 
lips. 
Diameter about one inch; axis four-fifths of an inch; diameter of 
the aperture three-fifths of an inch. 
Found by Mr. Drayton, at Illawarra, New South Wales. 
Remarkable for the great altitude of its outer whorl, and its large 
aperture. It is like H. Cakfornianus in form, H. albolabris in texture, 
and H. dadia in colour. It seems also to resemble H. tumzda, Pfeiffer. 
There can be no doubt that Mr. Drayton copied the animal pre- 
cisely as he saw it; and whether it be its ordinary or only its excep- 
tional mode of progression, it is certainly very extraordinary, and 
different from that of any other gasteropod; and the animal presents 
another of those grotesque forms, so many of which have already 
been found in New Holland. 
In the original description of this animal in the Proceedings of the 
Boston Natural History Society, it was supposed that it inhabited a 
- different shell, which was there named H. pedestris. An error has 
since been detected, and it is found that H. gulosa is the true shell, 
and H. pedestris is only a small specimen of H. Townsendiana. H. 
ruida, also, is probably an immature specimen of this latter species. 
17 
