240 MOLLUSCA. 
I am satisfied that two species have been confounded under the 
above name. The true T. tuberosum, is that figured by Lister and 
Martini, and is a West Indian species. It is short, gibbous, and 
decidedly waved and nodulous upon the back, with a short rostrum. 
The other is a Pacific shell, and is figured by Rumphius and Quoy, 
and by Reeve, asa variety. It is more elongated, with a rostrum of 
nearly double length, the back is rather wrinkled than nodulous, and 
the peculiar woven surface, which has obtained for it the name of 
“bed-tick” shell, among the Dutch, is strongly marked. It has a 
pale band, always seen by transmitted light within the aperture, and 
generally well-marked externally also; while the West India speci- 
mens seem to be destitute of it, and acquire a much greater amount of 
callus on the margins. I would propose for the elongated Pacific 
variety (which is found from the Sandwich to the Feejee Islands, and 
thence to the Moluccas), the name T°. productum. 
Triron anus (Lamarck), Encycl. Meth., pl. 413, f. 3. Anim. sans 
Vert., ix. 636. Quoy and Gaimarp; Voy. de l’Astrol., pl. 40, f. 6-10. 
Murex anus, Liy., &c. 
The locomotive disk of the animal is ornamented with large, pus- 
tular spots, with the interstices orange ; the anterior edge is tessellated 
orange and cream-colour; the tentacles are annulate with orange; the 
sides have similar markings, but much paler. 
Obtained at Lebuka, Feejee Islands. 
Figure 293, the locomotive disk of the animal, which, on com- 
parison, will be found to vary very considerably from that given in 
the Zoology of the Astrolabe. 
TRITON DisrorTUM (ScHuBEeRT and WaGNer), Suppl. to Mart. and 
Chemn., pl. 231, f. 4074. Lamarck; Anim. sans Vert., ix. 645. 
KreneER; lconog., pl. 17, f. 2. 
Anima. of a very pale; fleshy tint; head somewhat fawn-coloured, 
and tentacles annulate with the same. Foot small and short; head 
protruding ; siphon rather long. 
Obtained at the Paumotu Islands. 
