NOTES ON NtTDIBRANOHS. 
93 
from either the descriptions or figures. But the idea that the two 
forms are related is borne out by their structure, and they may 
prove to be merely colour varieties. 
Trevelyana (Kelaart). 
According to Bergh’s definition of this genus (Siboga, Exp. Opisthob. 
1905, p. 188, and elsewhere) the hermaphrodite gland is separate from 
the liver. 
“ Glandula hermaphrodisiaca a hepate discreta .” 
Though this can be said of many of the species already examined 
anatomically, it is not strictly true of all, e.g., T. crocea. But of the 
present species it is not true at all, and the generic definition must 
be modified. Still, even in this form the structure of the herma¬ 
phrodite gland is appreciably different from that usual in the Dorididce 
and less diffuse. It forms not a larger spread over the liver, but two 
thick coils of varying shape and length attached to the anterior and 
under surface of the liver. We should, I think, say that Trevelyana 
is characterized by having a more or less concentrated hermaphrodite 
gland, which sometimes takes the form of coils or flat lumps on the 
surface of the liver and sometimes of one or more masses (generally 
globular) separate from it. 
Trevelyana ceylonica (Kelaart). 
See Kelaart, Ann. and Mag. of Nat. Hist., 3rd Sei\, Voh I., 
pp. 257-8, 1858 ; c/. Bergh on T. rubromaculata in Siboga Expeditie, 
1905, Opisthob. p. 189-91. 
Pour specimens from Trincomalee of much the same size : length 
about 30 mm., height 15 mm., breadth 12 mm. With them is 
preserved some spawn, resembling a piece of string 3 mm. thick and 
loosely coiled. It has a coarsely granulated appearance, owing to the 
yellowish egg packets arranged within it, so that three or four lie in a 
transverse section. They each contain several eggs. 
The skin is soft and smooth, but here and there, especially near the 
tail, there are raised tubercular spots. The general shape is as in 
other Trevelyanas. As preserved the colour is dirty yellow, but 
Kelaart describes the animal as being white in life, with red spots 
on the back and red lines marking the axes of the branchiae and the 
margin of the foot. The rhinophore pockets are not much raised; 
no oral tentacles are visible. 
The most conspicuous feature in all the specimens is the branchial 
tuft, which is very large, most of the plumes being 8 mm. high, 
whereas in other species of Trevelyana these are generally not more 
than 4 mm. high in animals 40-50 mm. long. In all the specimens 
there are 10 large plumes set in a circle, open behind, though the 
interruption is not visible. At this point there are two smaller 
plumes set a little inside and nearer the anal papilla, and there are 
