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COLOUR IN NATURE 
CHAP. 
The Pigments of Crustacea 
i. The Lipochromes .—That the yellow, orange, 
and red pigments of the Crustacea are lipochromes 
was long since proved by the researches of Maly, 
Krukenberg, and others. Further, the lipochromes 
have been described as usually occurring in pairs—a 
red and a yellow together, which can be separated by 
the process of saponification. 
A superficial examination of the colours of 
Nephrops norwegicus , the Norway lobster, shows that 
the epidermis is bright red, and the shell orange-red, 
the colour of a boiled lobster. If, however, the shell 
be decalcified with dilute acid, it entirely loses its 
orange colour and becomes dull red—the colour of 
the epidermis. The interest of this change lies in 
the fact that while the boiled lobster, and those parts 
of the lobster’s shell which are not blue during life, 
are of a similar orange colour, the shells of deep-sea 
Crustacea tend to show such colours as “ blood-red ” 
“ deep crimson,” “ crimson-red,” and so on, and are 
usually not orange. Now the red lipochrome of the 
lobster or crayfish when removed from the shell very 
readily forms a combination with lime which is of 
orange colour. The shells of the deep-sea Crustacea 
contain little or no lime ; it therefore seems to me 
possible that the difference in colour between, say, 
Nephrops and one of the deep-sea Crustacea is not 
due to any difference in pigment, but only to the fact 
that in the former the lipochrome occurs associated 
with lime, and in the latter in the pure state. This 
is interesting, because Moseley during the voyage of 
