All from tlio 'Hiboga' 

 Expedition. 



1906.] OF .SOUTHERN INDIA AND CEYLON. 641 



123. Chr. Tnarpessa Tiei'gh. 



124. Chr. venusta Bergh. 



125. Chr. ophihrdmica Borgh. 



126. Chr. nodulosa Bergh. 



127. Chr. 2}(j('ntherina Bei'gh. 



128. Chr. papulosa ^iGv^x. V 



129. Chr. sihof/cn Borgb. 



130. Chr. inopinata Bergb. 



131. Chr. lactea Bergb. 



132. Chr. himaensis Bergb. 



133. Chr. virgala Bergb, 



Basedow and Hedley have described Chr. epicurea under 

 the name of Hypselodoris (Trans. Roy. Soc. South Australia, 

 vol. xxix. 1905, pp. 141 & 153), and wish to substitute this 

 generic name (Stimpson, Proc. Ac. ISTat. Sci. Philadelphia, vii. 

 1855, p. 388) for Chromodoris. It would be a pity to drop an 

 accepted and widely used name like Chromodoris in favour of one 

 which has never been in use and which was only tentatively 

 proposed for an imperfectly described animal. But in any case 

 8timpson's name (1855) cannot claim priority, for Ehrenberg's 

 Glossodoris, Fterodoris, and Actinodoris (1831) are admittedly 

 Ohromodorids, though for the sake of convenience the names 

 have not been revived (see Bergh, " Kritische Untersticbung dor 

 Ehrenberg'schen Doriden," Jahrb. d. d. malakozool. Ges. iv. 1877, 

 pp. 45-70). 



The list of 133 Ohromodorids will no doubt be found to contain 

 many synonyms. Many of the tropical species are known only 

 by their external coloration, and when it is possible to examine 

 many specimens the coloration generally proves to be variable. 

 Very often different colours become predominant in different 

 individuals. Chr. diardii var. nigrosiriata is generally bluish 

 grey with faint blotches of pale yellow, but sometimes the yellow- 

 is developed at the expense of the blue and the whole animal 

 a,ppears to be lemon-colour. Chr. qitadricolor sometimes looks as 

 if it were light-coloured with black bands, and sometimes as if it 

 were black with light bands. A difference of intensity oftens 

 produces a difference of colour : thus, red becoming paler may 

 fade into orange, deep yellow, light yellow, and yellowish white, 

 or becoming darker it may be intensified into reddish brown or 

 lake, purple, purplish black, and black. In pale specimens 

 markings, especially borders, have a tendency to disappear ; in 

 full-coloured specimens they tend to multiply, and scattered dots 

 may collect and fuse so as to form blotches. Lines sometimes 

 break up into a row of dots, but on the whole the distinction 

 between the spotted and striped forms seems more persistent tha,n 

 others. Though these variations of tint and pattern show that 

 we must not expect uniformity in a species, it is also clea,r that 

 unless the resemblance in colour is striking and detailed, it is by 

 no means safe to concbide that similar forms are specifically 



43* 



