1869.] MR. W. S. KENT ON A NEW NUDIBRANCH. 109 
while the abdominal parts are light yellowish. As they grow older 
they alter little. 
4. Males a couple of years old or more become of a rich brown 
shade on the back and sides, and lighter or yellowish beneath. Old 
males alone are maned. 
5. There is a sparse underwool on the young, which sensibly di- 
minishes with age. 
6. The skulls of the adult male and female differ considerably, the 
latter being comparatively the narrower of the two—the former pos- 
sessing a somewhat different form of teeth, besides proportionally 
immense canines. 
7. The teeth of Otaria jubata are occasionally subject to a pecu- 
liar wearing, of a median constricted character. 
8. The sexes differ in size, the males attaining far the largest growth. 
9. Between the female and male of this species there is a wide 
difference as regards the stretch of the pectoral flippers. In the skin 
of the male the breadth from tip to tip of the fore flippers is equal 
to or greater than the length of the body; in the female the reverse 
obtains. This fact points to greater strength and swimming-power 
in the former. 
10. It appears that the Elephant-Seal (Morunga elephantina) is 
now only rarely met with in the Falklands. 
11. The bones of the pectoral limb of the Fur-Seal of commerce 
(Otaria nigrescens, Gray) differ from those of the Sea-lion (Otaria 
jubata). 
DESCRIPTION OF PLATE VII. 
Fig. 1. Adult male Ofaria jubata, from the skin No. 1. The abraded surfaces 
have not, however, been delineated. 
2. Adult female of the same species, from the skin described as No. 2. 
3. Young O¢aria jubata, about four months old, referred to as No. 10 in 
the preceding list. 
5. On a new British Nudibranch (Hmbdletonia gray). 
By W.S. Kent, F.R.M.S. 
(Plate VIII.) 
The last October excursion to the Victoria Docks of the Quekett 
Microscopical Club afforded me the pleasure of capturing, in some 
quantity, a minute representative of the Nudibranchiate Mollusca. 
It belongs to Alder and Hancock’s genus Eméletonia, which is 
characterized as follows :—‘‘ Head terminal, furnished with two flat- 
tened lobes, broadly expanded laterally. Tentacles two in number, 
linear. Branchiz papillose, placed in a single or double row down 
each side of the back, alternating posteriorly.” Three species are 
described by the authors above quoted, viz. 2. pulchra, EF. minuta, 
and E. pallida. Of these, Embletonia pallida is the most closely allied 
