Thus far, our information respecting the crayfish is such as would be forced upon anyone who dealt in crayfishes, or lived in a district in which they were commonly used for food. It is common knowledge. Let us now try to push our acquaintance with what is to be learned about the animal a little further, so as to be able to give an account of its Natural History, such as might have been furnished by Buffon if he had dealt with the subject. There is an inquiry which does not strictly lie within the province of physical science, and yet suggests itself naturally enough at the outset of a natural history. The animal we are considering has two names, one common, _Crayfish_, the other technical, _Astacus fluviatilis_. How has it come by these two names, and why, {12} having a common English name for it already, should naturalists call it by another appellation derived from a foreign tongue? The origin of the common name, “crayfish,” involves some curious questions of etymology, and indeed, of history. It might readily be supposed that the word “cray” had a meaning of its own, and qualified the substantive “fish”—as “jelly” and “cod” in “jellyfish” and “codfish.” But this certainly is not the case. The old English method of writing the word was “crevis” or “crevice,” and the “cray” is simply a phonetic spelling of the syllable “cre,” in which the “e” was formerly pronounced as all the world, except ourselves, now pronounce that vowel. While “fish” is the “vis” insensibly modified to suit our knowledge of the thing as an aquatic animal. Now “crevis” is clearly one of two things. Either it is a modification of the French name “écrevisse,” or of the Low Dutch name “crevik,” by which the crayfish is known in these languages. The former derivation is that usually given, and, if it be correct, we must refer “crayfish” to the same category as “mutton,” “beef,” and “pork,” all of which are French equivalents, introduced by the Normans, for the “sheep’s flesh,” “ox flesh,” and “swine’s flesh,” of their English subjects. In this case, we should not have called a crayfish, a crayfish, except for the Norman conquest. On the other hand, if “crevik” is the source of our {13} word, it may have come to us straight from the Angle and Saxon contingent of our mixed ancestry.