Mollusca Nudibranchiata (Ascoglossa). 
i8i 
examined, it will be seen that they show the rhinophores in a similar position, 
although the arrangement does not look unusual because there are practically no oral 
tentacles in these animals. 
Dr. Annandale observes that the various tentacles and processes are greatly 
distorted in the preserved specimens. It is true that none of them resemble his 
sketch but still the following details seem clear. The rhinophores are moderately 
long and moderately stout, though thin compared with the cerata. They seem to be 
round and smooth, as usual in the genus : they are certainly not auriculate and I 
could find no clear traces of a groove or channel. In many specimens the oral 
tentacles have shrivelled up but in some are still visible as distinct pointed processes. 
In some specimens the anterior margin of the foot appears to be grooved and both 
the upper and lower edges of this groove to be produced into tentacular processes. 
Though the precise structure and relation of these parts cannot be determined with 
certainty, it is clear that the tentacular appendages are more in number and more 
pointed than in other species of Stiliger, e.g. heilulus. 
Fig. I. — Left side of the head. FiG. 2. — One of the cerata. 
(From drawings made by Dr. Annandale from the living animal.) 
The cerata still retain the general shape and colour described by Dr: Annandale. 
They are very easily detached and many specimens are quite bare, but have no scars 
on the back sufficiently clear to mark the position and number of the detached 
processes. A complete specimen looks superficially as if it were entirely covered with 
cerata pointing in all directions, but Dr. Annandale is no doubt right in saying that 
they are arranged on either side in two alternative rows, that is four rows altogether, 
there seem also to be smaller cerata placed irregularly outside the rows. The number 
of cerata in a given longitudinal row is not easy to determine as most of the speci- 
mens are bent or contracted but probably varies from 12 to 16. The opaque white 
spots on the cerata are very noticeable and have the appearance of being raised. 
The hepatic diverticulum within is twisted and covered with knobs but does not ap- 
pear to be strictly speaking branched. Occasionally three or four very large cerata 
occur on one animal. It is not plain if this inflation is natural or due to the preserv- 
ing fluid. 
Though a complete specimen often looks like an almost circular bunch of cerata, 
the body is really slender and tapers to a point behind. The pericardium is not very 
