Hawaiian Opisthobranchiates — OsTERGAARD 
Edmondson for his generous aid in securing 
specimens. 
Melibe pilosa Pease 
Fig. 17 
Melihe pilosa Pease, Zool. Soc. London, Proc. 
I860: 34. 
The description by Pease fits so closely the 
specimen I have figured that it is quoted here: 
Elongate, smooth, widest anteriorly, and tapering 
to a point behind. Sides convexly rounded, and the 
back arched. Foot linear, grooved, extending the whole 
length of the body, and acute at both ends. Six pairs 
of thick tuberculated lobes along the back, the anterior 
pair opposite, the others alternate to one another, the 
last at the tip of the body. These lobes are easily 
deciduous, contracted at their bases, truncated above, 
convex outside, and flattened on the inner surface. 
Frontal veil very large, semi-globular, much inflated 
above; united beneath the head, forming a continuous 
margin, which is closely fringed. Mouth proboscidi- 
form, and the orifice vertical. Tentacles on the posterior 
portion of the veil rather remote, small, ovate, closely 
and transversely lamellated and retractile into long 
trumpet-shaped sheaths, which are furnished with lac- 
iniated appendages. Everywhere with small, soft, 
branched, tentacular processes. Colour fawn, subtrans- 
lucent, more or less crowded with whitish, which, under 
the lens, has the appearance of minute dots. Body 
punctured with brown, which are most conspicuous 
along the flanks. Tubercles on the lobes brown. Foot 
pale. 
Length 2Vi inches. 
These animals were found among seaweed, in the 
upper region of the laminarian zone, and when placed 
in a basin of water were very active, swimming by 
suddenly curving the head and tail laterally, so as 
nearly to touch one another. When slightly disturbed 
they could cast off one or all of their lobes. The length 
of their lobes varies much, being in some as large again 
as in others; they may be consequently reproduced, 
after being cast off. Their foot cannot be used for 
creeping on a flat surface, but is well adapted for 
clasping sea-weed. 
The above description of the habits of the 
animal agrees with my observation based on 
a considerable number of specimens found 
on the reefs near shore along leeward Oahu, 
principally at Waikiki and Kahala. Specimens 
have been found in September, February, 
June, and December. 
The specimen of M. pilosa that I have fig- 
ured measures 3 centimeters in length. Other 
specimens reached the length of 5 centimeters, 
Fig. 17. Melibe pilosa Pease, a , Dorsal aspect; b, de- 
tail of tentacle; c, oral aspect of frontal veil; d, lateral 
aspect, (a, d , X 2.4.) 
thus approching the size of Pease’s "2Vi 
inches” (6 cm., 3 mm.). 
While several of the animal’s habits have 
