48 A HISTORY OF RECENT CRUSTACEA 
of which has from of old been fancifully called ‘the lady 
in the chair.’ The character of all the internal organs of 
Fic. 1.—A lobster’s stomach opened to show the teeth, the central one of which has 
been supplied with eyes, nose, and mouth, to represent ‘the lady in the 
chair’ [Herbst] 
a crustacean, as exemplified in the crayfish, has been 
already discussed in detail by Professor Huxley in a pre- 
vious volume of this series. It may here, therefore, suffice 
to recall that in a crustacean the heart is dorsal, the nerve- 
chain, with the exception of the brain, ventral, and the 
alimentary canal central, having in proximity the hepatic 
lobes or liver, and the testes and ovaries. Some of the 
more or less striking peculiarities which prevail in different 
groups in regard to these organs are reserved for mention 
as occasion offers in the description of the several sub- 
orders and their families. 
The following table supplies a synopsis of all the 
leading groups of the Crustacea. The literal meaning 
of the various names has been explained in the first 
chapter :— 
