548 SIR CHARLES ELIOT. 



This genus was instituted by Bergh for a single specimen (iV. citrina) from Rarotonga. 

 I have obtained another (iV. minor) at Zanzibar, which seems specifically distinct, and the 

 present collection contains a third. All three forms are identical in their anatomy, and 

 are also all of a yellow colour, but they differ externally in the contour of the body and 

 the subdivisions of the branchial valve. It may perhaps be proved that they represent 

 merely varieties or different ages, but provisionally they must be classed as separate species. 

 N. citrina appears to have a single median ridge from the rhinophores to the branchiae, 

 a branchial valve with about 8 lobes, and a fairly distinct tail. In N. minor the tail is 

 not distinctly marked off from the rest of the body, and the whole animal seen dorsally 

 somewhat resembles Phyllidia. The inconspicuous branchial valve is three-lobed, and though 

 the surface of the back is somewhat irregular there are no distinct longitudinal ridges. 

 The colour is lemon-yellow, with black lines, not spots. In N. gardineri the long tail is 

 plainly distinguished from the body : there are four dorsal ridges : the branchial valve consists 

 of three lobes, each of which is elaborately subdivided: the colour is yellowish, with a few 

 round black spots. 



Notodoris is evidently allied to Aegirus (found on the British and E. European coasts) 

 and to the little known Triopella, both of which are of hard consistence, and have the 

 branchiae and rhinophores protected by tubercles. This little group of three genera seems 

 to stand near the cryptobranchiate Dorids, inasmuch as the teeth are not differentiated 

 but uniform, and the branchiae capable of being concealed. They are not retractile into 

 a pocket, but the same result is produced by the protecting valve, which shuts down over 

 them. Nothing is known of the habits of these animals. In captivity N. minor was quite 

 inert, and did not make any movement. With Mr Gardiner's specimen is a piece of hard, 

 yellow sponge. There is no note, but as the colour and consistency of the sponge closely 

 resemble those of the nudibranch it is highly probable that the latter frequent it. 



5. N. gardineri n. sp. (fig. 7). 



One specimen from Hulule, Maldive Islands. Length 3"35 cm. : breadth at widest part '9 : 

 height at highest part 1'2. Colour, uniform dirty yellow, with a few vivid black spots on 

 the upper but not on the under surface. Frontal veil large and rounded. The flat sole 

 ■occupies the whole under surface of the body. There is no distinct mantle edge, but a ridge 

 runs from each end of the frontal veil to the branchial valves. Between these are two more 

 ridges, which are again connected by smaller ridges, shaped like the letter Y. The depressions 

 between the ridges are smooth, but the tail and other parts of the body covered with rough 

 and rather large tubercles. The radula (as in the other species) consists of numerous uniform 

 hamate teeth, with a rudimentary additional denticle. Their form is exactly that given in 

 Bergh's plate {I. c. PI. IX. 39). The visceral mass and reproductive organs were too much 

 hardened to admit of any examination, but in iV. minor the verge appeared to be trifid at 

 the extremity and covered with rows of small tubercles. The rhinophore openings are closed 

 by their valves. The large branchial valve (fig. 8) is composed of three lobes, each elaborately 

 divided and furnished with numerous spatulate processes. In order to preserve the specimen 

 the internal parts were taken out through the foot and the frontal veil and branchial valve 

 not removed. Hence the gills were not examined. 



