JAPANESE NUDIBBANCHS. 29 



mantle edge. The branchiae are 18 in the larger specimens, 10 

 in those of moderate size and only 8 in the two smallest. They 

 evidently increase in number with age. 



The labial armature is composed of distinctly bifid rods. In 

 the larger specimens the formula of the r adula is about 75x70. 

 0.70. The teeth bear 5-7 denticles, which become much more 

 distinct near the end of the rows, but the outermost teeth of all 

 are merely plates with jagged edges. 



Chvomodoris inavenzelleri Bergh. 



Bergh : Beiträge zur Kermtniss der japanischen Nuclibranchien, ii, Verb. k. k. Zool. Bot. Ges. 

 Wien, 1881, pp. 219-221. 



(Plate II., fig. 9). 



Two specimens from Misaki about two centimetres long and 

 also two coloured drawings made in 1895 and 1907 respectively, 

 the latter representing the present specimens when alive. It 

 depicts a flattish and moderately broad Chromodoris of a slate- 

 blue colour. The margin of the mantle is marked by a lemon- 

 coloured border and a continuous line of the same hue runs down 

 the centre of the back from the rhinophores to the branchiae. On 

 either side of this continuous line is a similar but broken line. 

 On the sides of the body are lemon-coloured spots. There are 

 also a few scattered black spots on the back. The rhinophores 

 are blue in the lower and bright red in the upper part. The 

 branchiae are eleven, bright red outside and white inside. The 

 earlier drawing is similar in essentials but the ground colour is 

 greenish rather than blue and there are numerous dark spots on 

 the back and sides. 



The preserved specimens agree, so far as their present 

 condition admits of a comparison, with the drawing of 1907 and 

 also with Bergh' s description. The radula is as described by 

 him except that I found no thickenings on the rhachis and that the 

 teeth next to the rhachis often bear 4 and not merely 3 denticles. 



