516 APPENDIX. 
in the right one, for instance in Tr. serpuloides. The same 
inequalities exist in the neck-lappets of the larger Trochi. I 
have thus removed all aberrations between the organs of the 
larger and these minute but perfect Trochidans. I believe 
there are only three vibracula on each side the opercular lobe, 
instead of four as I have elsewhere stated, but I do not vouch 
that there may not be four in one of the above species. 
PHASIANELLA PULLUS.—(P. 820.) 
Exmouth, July 1854. 
As I have several important additions and corrections to 
make in my account of this animal, I have thought it best to 
give a general description of it, as the alterations will thereby 
be rendered more intelligible. 
Shell of five obliquely striated, almost smooth, tumid, por- 
cellanous volutions, separated by a fine sutural line, variously 
painted with all imaginable hues of colours, forming in many 
specimens a splendid tout ensemble: the body whorl equals in 
size all the rest. The aperture is suboval, outer lip sharp, 
and much advanced beyond the columellar side. 
Animal.—The mantle exactly lines the shell, and is of the 
palest hyaline sea-green. Muzzle very short, cylindrical, 
finely wrinkled, mottled with red-brown blotches, sometimes 
marked with transverse green stripes, and at others with longi- 
tudinal streaks of the same colour, on a yellow or pale red 
ground ; its termination or disk is subcircular, finely serrated 
atthe margin, and has a crosial oral fissure; from this the 
animal often protrudes the corneous jaws, which with the 
lingual riband are supported by greenish fleshy plates; the 
under surface of the disk is marked with red streaks on a 
white ground. The tentacula are pale yellowish-white, long, 
pointed, flattish, crowded with fine sete, and are m constant 
vibration. The eyes are external, on distinct yellow, white, 
or green pedicles. The neck-lappets are white, pale, or grass- 
green subcircular membranes; the right is the largest, mar- 
gined with 12-15 distinct white or green cirrhi, of almost 
equal length, and fimbriated at the sides; the left has only 
