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 ; Camuiaro, or Gamharo, 

 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 

 oi Astacus JiuviatUis. 



But granting the exi^ediency 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 

 simpl}' John, James, Pet^r, 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, 



