Nudtbranchiate Mollusca in the China. Sea. 93 
singularly enough, the Chromodoris which I had already found 
at the Pescadores; the next I recognized as an old acquaint- 
ance of Haitan Straits, and I began to think there was nothing 
new—in Labuan at least; but I ultimately discovered a new 
species of Doris, beautifully marked with longitudinal lines 
alternately nearly black and white, the tentacles and branchiz 
being also mottled to match this colouring, the whole mantle 
and foot having a border of orange. ‘This species was at that 
season of the year (August) pretty common; and I found it 
at Labuan, and also on both the small adjacent islands before 
mentioned. | 
The gentleman who had described to me the appearance of 
certain species which he averred having seen in his shell- 
collecting rambles, kindly accompanied me to the spot; and 
we both searched in every direction, but without success, and 
I was obliged to leave them to my successors to discover and 
bring to light. Probably it was not the right season. Upon 
one of the small islands I met with a large mottled-grey and 
tubereulated Dorid, 4 inches long, with capacious tentacles and 
expansive gill-tufts (not unlike Doris tuberculata), which exhi- 
bited a singular habit. Several specimens which I took home 
for examination, after a short time performed a spontaneous 
2 gale of the mantle close round the body, as cleanly as 
if done with a pair of scissors, after which they soon decayed. 
At first I was inclined to attribute this circumstance to a large 
Pyrula, which was in the same vessel; but having removed 
the other specimens into a separate vessel of clean water until 
I should have time to attend to them, [ found the next day 
that they also had amputated their mantles. It appeared in- 
deed to be a suicidal act, produced probably by the fouling of 
the water, and analogous perhaps to the breaking-up of Coma- 
tule and the self-evisceration of Holothurie. 
At 3 pa I found a variety of Doridopsis rubra, a fine 
rose-coloured species which occurs among the Ceylon Nudi- 
branchs of Kelaart, and also among the Madras Nudibranchs 
described by Messrs. Alder and Hancock, and is perhaps syno- 
nymous with a Cuvierian species, Doris solea. It is not a 
little curious and interesting to find such small and delicate 
animals existing in places separated by so many hundreds 
(and, in some instances, thousands) of miles of trackless ocean ; 
and there seems scarcely any limit to the geographical range 
of these creatures, which evidently require abundant food, 
__whose locomotive powers are very limited, and whose soft 
__ bodies are ill calculated to resist much rough treatment by the 
_ waves. Probably their dispersion has mainly been effected 
by their multitudinous ova; and yet in many cases their 
Ann. & Mag. Nat. Hist. Ser.4. Vol. i. 8 
