INTRODUCTION. 



WHAT ARE SHELLS? 



De. Johnson gives us no less than eight different meanings for 

 the word Shell. First, he calls it 'The hard covering of any- 

 thing; the external crust.' Second, 'The covering of a testaceous 

 or crustaceous animal.' And here we may stop, for this is just 

 the signification which has to do with our subject; so let us turn 

 the sentence inside out, and see what we can make of it. We 

 all know what a covering is — an outer coat, a case, a protection 

 from iiijury, a husk, a crust, a — in short, a shell, — neylL or scell, 

 as our Saxon forefathers called it; schale, as the G-ermans now 

 term it. No Latin nor Grreek here, but the good old Saxon 

 tongue, somewhat rough and rugged, perhaps, but stout and sturdy, 

 and honest and serviceable; a kind of language to stand wear and 

 tear, like a pair of hob-nailed shoes, with little polish, but useful, 

 yes, very useful! Well, we have got so far, now comes a hard 

 word — Tes-ta-ce-ous, what can it mean? It is proDounced ^e^-^a- 

 shus, comes from the Latin testaceus — having a Shell, and means 

 consisting of, or composed of shells; so we find that a iestaceon 

 is a shell-fish, and tedaceology is the science of shells. Johnson's 

 second meaning of the word testaceous is 'Having continuous, not 

 jointed shells, opposed to crustaceous.' So we find that some 

 naturalists call those testaceous fish, "whose strong and thick shells 

 are entire and of a piece, because those which are joined, as the 

 lobsters, are crustaceous." 



Now some of the true testaccan have shells in more than one 

 or two pieces, and therefore this last explanation of the term is 

 rather calculated to mislead a learner; but we shall explain presently 

 wherein the diflerence consists between them, and the Crus-ta-ce- 

 ous, or, as we pronounce it, Inis-ta-s/ms, fish consists. Here is 

 another long word, it comes from the Latin crusta, a word of 

 many meanings, all having reference to an outer coat or covering. 

 My readers know all about pie-crust, and have perhaps heard ^a 



