SIR C. ELIOT—REPORT ON THE NUDIBRANCHS. 93 
much more the appearance of Scyllwa than the adult animal. The chief 
differences are :—(1) In Crosslandia the liver is only slightly, if at all, ramified. 
In the present specimen no branches at all were found, bui it is probable 
that individuals (as in Dendronotus and Bornella) show considerable variation 
in this respect. In Scyllea the liver is considerably ramified, though it does 
not penetrate the rhinophores and papille to the same extent in all species. 
(2) In Seyllwa there are on either side two dorsal processes quite distinct 
from one another. In Crosslandia the two are joined. The dorsal outgrowth 
thus formed is deeply bilobed in the young animals; in the adults the 
bilobation more or less completely disappears and a single wing-like ex- 
pansion is the result. I cannot find in any description or figure * of the 
species of Scyllea a record of such a formation, nor have I come across it in 
examining a great number of specimens labelled Scyllwa pelagica and coming 
from both the Atlantic and Indo-Pacific Oceans. It must therefore, I think, 
be regarded as a distinct character of at least specific importance. The 
* Possibly the figure of Seyllea Hookeri (no. 203 in Mrs. Gray’s ‘ Figures of Molluscous 
Animals’) may be the young of this form. But nothing seems to be known of the name 
except this not very distinct figure, 
o- 
