At the present time, therefore, while the recognised technical name of the crayfish is _Astacus fluviatilis_, that of the lobster is _Homarus vulgaris_. And as this nomenclature is generally received, it is desirable that it should not be altered; though it is attended by the inconvenience, that _Astacus_, as we now employ the name, does not { 14} denote that which the Greeks, ancient and modern, signify, by its original, _astakos_; and does signify something quite different.
Finally, as to why it is needful to have two names for the same thing, one vernacular, and one technical. Many people imagine that scientific terminology is a needless burden imposed upon the novice, and ask us why we cannot be content with plain English. In reply, I would suggest to such an objector to open a conversation about his own business with a carpenter, or an engineer, or, still better, with a sailor, and try how far plain English will go. The interview will not have lasted long before he will find himself lost in a maze of unintelligible technicalities. Every calling has its technical terminology; and every artisan uses terms of art, which sound like gibberish to those who know nothing of the art, but are exceedingly convenient to those who practise it.
In fact, every art is full of conceptions which are special to itself; and, as the use of language is to convey our conceptions to one another, language must supply signs for those conceptions. There are two ways of doing this: either existing signs may be combined in loose and cumbrous periphrases; or new signs, having a well-understood and definite signification, may be invented. The practice of sensible people shows the advantage of the latter course; and here, as elsewhere, science has simply followed and improved upon common sense. { 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 technical terms for the same thing. They need a universal language; and it has been found convenient that the language shall be the Latin in form, and Latin or Greek in origin. What in English is Crayfish, is _Écrevisse_ 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_.