NOTES ON NUDIBRANCHS. 
81 
The animal is elongate and narrow, about 14 mm. long and 3-4 
mm. broad at different points. The right oral tentacle and right 
rhinophore are very large, more than 5 mm. long, whereas the 
corresponding organs on the left are not half the size. It is not clear 
whether this conformation is a monstrosity or due to distortion by 
the preserving fluid. The corners of the foot are rounded. The 
rhinophores are quite smooth and show no trace of perfoliations. 
The genital orifices lie below the dorsal margin, about 2 mm. from 
the head, and the anal papilla about 2 mm. further back in the line 
of the margin. Most of the cerata are detached. They were set 
on seven low oblique ridges. The anterior ridges seem to have borne 
8-9 cerata, the others fewer. The largest cerata are about 4 mm. 
long. The margin of the foot is expanded, and posteriorly the foot 
is prolonged behind the body in a tail. 
The jaws bear a single row of very distinct denticles with squarish 
tips. The radula consists of a single row of 22 teeth of the horse¬ 
shoe type. The posterior limbs are long. The central cusp is large 
and long : on either side of it are four or five (generally five) long, 
thin, lateral denticles. 
No armature was found in the genitalia. 
This animal seems referable to Gratena , Bergh, but as I have 
indicated elsewhere (Journ. Mar. Brit. Assn., 1906, pp. 363-6) the 
genera Cuthona , Cuthonella , and Gratena seem to me not distinguish¬ 
able by any valid generic characters. Species should therefore be 
described under the oldest generic name, viz., Cuthona. 
The present species is nearly allied to, and possibly identical with, 
the later (1905) Cratena cucullata, Bergh, from Gisser island in the 
Malay Archipelago, near Timor. 
Cr. cavancce, B., Cr. pusilla, B., and Cr. bylgia, B., all seem to 
be allied species. 
Scyllcea marmorata (A. & H.). 
See A. & H. I., p. 136, and Eliot I., pp. 675-6. 
? = Sc. pelagica var. orientalis , Bergh, Mai. Unt. in Semper’s 
Reisen., pp. 339-41. 
One specimen from Trincomalee. It is 15 mm. long and of a pale 
brown. The epidermis detaches itself very easily, and has mostly 
disappeared from the sides of the body, but on the back and inside 
the cerata it can be seen that the pale brown ground was elegantly 
marked with darker marblings. Traces of a light margin still 
remain on the rhinophore sheaths, cerata, and caudal crest. There 
is a row of 4-5 white tubercles on either side of the body. 
The animal is much like Alder and Hancock’s figure, except that 
the tail is shorter. The cerata are rounded, not jagged or indented. 
The rhinophore sheaths and caudal crest are not large. The 
branchial tufts are ample and luxuriant, pellucid, but marked with 
fine brown lines. They are found on the inner side of the cerata, on 
