THE CHAEACTEES OF THE DEEP-SEA FAUNA 63 



been found in the abysmal zone, namely, Bathydoris 

 abyssorum, is described by Mr. Murray as follows : 

 ' The body of the living animal was gelatinous and 

 transparent, the tentacles brown, the gills and pro- 

 truding external generative organ orange, the foot 

 dark purple.' 



Among the Crustacea various shades of red are 

 the prevailing colours. ( The deep-sea types, like 

 Gnathophausia, Notostomus, and Glyphocrangon, 3 says 

 Agassiz, * are of a brilliant scarlet ; in some types, as 

 in the Munidas and Willemoesige, the coloration tends 

 to pinkish or yellowish pink, while in Nephrops and 

 Heteroca/rpus the scarlet passes more into greenish 

 tints and patches.' But perhaps the most remark- 

 able point in the colour of the Crustacea is that which 

 immediately follows the paragraph I have just quoted. 

 ' The large eggs of some of the deep-sea genera are 

 of a brilliant light blue, and in one genus of Macrura 

 we found a dark metallic blue patch on the dorsal 

 part of the carapace in marked contrast to the bril- 

 liant crimson of the rest of the body.' 



1 In the recent researches of the ' Investigator ' a few Crustacea 

 of rather exceptional colour were found. Whilst the great 

 majority of them are described to be pink or red in colour when 

 alive, Gnatlwpliausia bengalensis is deep purple lake, Hallporus 

 neptunus lurid orange, and Aristae us coruscans bright orange. 



