THE USE OF THE BINOMIAL NOMENCLATURE. 15 
Moreover, while English, French, German, and Italian 
artisans are under no particular necessity to discuss 
the processes and results of their business with one 
another, science is cosmopolitan, and the difficulties of 
the study of Zoology would be prodigiously increased, if 
Zoologists of different nationalities used different tech- 
nical terms for the same thing. They need a universal 
language ; and it has been found convenient that the lan- 
guage shall be the Latin in form, and Latin or Greek in 
origin. What in English is Crayfish, is Ecrevisse in 
French; Flusskrebs, in German; Cammaro, or Gambaro, 
or Gammarello, in Italian: but the Zoologist of each 
nationality knows that, in the scientific works of all the 
rest, he shall find what he wants to read under the head 
of Astacus fluviatilis. 
But granting the expediency of a technical name for 
the Crayfish, why should that name be double? The 
reply is still, practical convenience. If there are ten 
children of one family, we do not call them all Smith, 
because such a procedure would not help us to dis- 
tinguish one from the other; nor do we call them 
simply John, James, Peter, William, and so on, for 
that would not help us to identify them as of one family. 
So we give them all two names, one indicating their 
close relation, and the other their separate individuality 
—as John Smith, James Smith, Peter Smith, William 
Smith, &c. The same thing is done in Zoology; only, 
in accordance with the genius of the Latin language, 
