312 MOLLUSCA. 
smooth, orange-coloured, crescentic area appears in front of the shell, 
which is evidently covered by the shell when retracted. Mouth far 
behind the anterior limit of the animal; lips circular and corrugated, 
and surrounded by oblong radiating foliations. 
According to notes made by Dr. Pickering, there seemed to be none 
of the numerous stomachs of Aplysia. The genital orifice seemed to 
be near the base of the right tentacle, though no external opening was 
discovered, nor any groove as in Aplysia; but the internal organs 
were seen to be voluminous. Vent at the opposite end of the body, 
tubular and projecting ; heart on the forepart of the back, with a strong 
muscular ventricle. Pharynx large, and provided with very powerful 
muscles like fowls’ gizzards; throat very large, and lined for some dis- 
tance by a tough membrane, having numerous fine, enamelled ruge 
adapted for rasping and triturating food. Intestinal canal short, with 
a ligamentous enlargement or stomach at its anterior portion; rectum 
filled with a substance resembling sponge, perhaps a hydrophyte. Its 
relations would seem to be with Pleurobranchus rather than with 
Natica or Aplysia. 
Obtained at the Sandwich Islands, by Mr. Drayton. 
In the Voyage of the Bonite (pl. 27), the animal of Umbrella Indica 
is represented as blotched with chlorine green, not tuberculated ; the 
branchie as white and not projecting beyond the shell; the tentacles 
as acute, with no projecting lobes in front; beneath straw-coloured, 
and with the shell more rounded. The shell of this animal grows to 
a very large size, is quite solid and heavy, coarsely striate within, and 
usually deep golden yellow. It is probably different from the true 
U. Indica, and might bear the name employed by Gmelin, of U. wm- 
bellatu. 
Figure 408, dorsal view of the animal and shell; 408 a, anterior 
portion of the animal beneath, showing the mouth. 
CuiTon QuErcINus (Gould). 
Testa depressa, ovalis, vix carinata, quercina, maculis olivaceis nubecu- 
lata; valvis subrostratis ; arets laterahibus viz elevatis, longitudinaliter 
