424 PERCY SLADEN TRUST EXPEDITION. 



surface thickly covered with small papillae. Ground-colour white, but thickly mottled 

 with various shades of brown. These mottlings are concentrated in places and form 

 twelve irreo-ular nearly black spots. On the underside of the mantle are large 

 purplish spots, and on the foot are smaller confluent ones. The oral tentacles are 

 cylindrical. The sheaths of the rhinophores are completely closed and form moderately 

 prominent mounds. The branchiag are six, tripinnate, and mottled brown. 



The labial armature consists of two triangular plates : the top end is moderately 

 broad, the lower end pointed. They are formed of small rods, not hooked or cleft. 

 The teeth are all simply hamate, and the formula of the radula is 26 X about 45 . . 45. 



J), modesta is nearly allied to D. cebuensis, and perhaps merely a darker variety of it. 

 But there are some small differences in the buccal parts. 



12. Discodoris cebuensis, Bergh. 

 Bergh, Mai. Unters. in Semper's ReiseUj Heft xii. p. 526. 



Two specimens from Coetivy. 



Both are of a pale colour and have extremely wide mantle-margins. The larger, 

 which is 39-5 mm. long, 20 mm. broad, with a mantle-margin measuring 8 mm. at the 

 sides and 11 mm. at the head and tail, is almost pure white, with traces of brown 

 colour in the middle, of the back. The other, which is similarly proportioned, but only 

 15 mm. long, is bluish white with many spots of various shades of purple, which are 

 themselves formed by an aggregate of smaller spots. In both there are a few brownish 

 flecks on the undersides. 



The animals are flat and soft. The integuments are spiculous, and the dorsal surface 

 is covered with small spiculous tubercles. 



The labial armature consists of two plates set so close together that they almost form 

 a circular band composed of small rods. The formulae of the two radulse are respec- 

 tively 20x30.0.30 and 17x20.0.20. The teeth are large and hamate. Those 

 nearest to the rhachis have a small denticle at the base of the shaft. The outermost are 

 small and erect. 



These specimens seem to represent a light variety of J), cebuensis. I have compared 

 them with the type deposited in the Copenhagen Museum. 



13. Kentrodoris rubescens, Bergh. 

 Bergh, Mai. Uuters. in Semper's Reisen, Heft x. p. 411. 



One specimen labelled " Salomon." It is 67 mm. long and 22 mm. broad. The 

 skin is quite soft and smooth to the touch, but under a lens is seen to be covered with 

 very minute papillae. The ground-colour of the dorsal surface is greenish grey, still 

 showing a tinge of pink, which was stronger when the specimen was first received. 

 Over this pinkish ground are scattered a considerable number of short lines about 

 4 mm. in length. They are more distinct and thicker on the head and the tail-end of 

 the mantle, where they even form spots. There are a few of them on the underside of 

 the mantle and on the sole of the foot, which shows traces of having been pink. 



