"Oh, I told you they fitted in a case; but when the fly is done sawing, it uses the saws to put the egg in the place cut for it, and then it draws the saws almost entirely into the case, and drops upon the egg a sort of frothy stuff like a drop of soap-lather." "What is that for?" "I suppose it is to glue the egg fast, or else to keep the juices in the bush from hurting it." "Well, this is a curious fly, Uncle Philip." "It is strange, boys, because you never heard of it before; but it is a cunning fly, as well as a curious one." "What does it do, Uncle Philip?" "Why, when it is frightened, it will fold up its case and saws under its body, and draw up its legs, and pretend to be dead; and then it will not move, even if you stick a pin through it." "Can you tell us any thing more about this fly?" "Nothing very strange, boys; but we have found out _two_ tools, I think, a saw and a rasp, and that is enough for one poor little fly to give us. Here, boys, are pictures of these saws; I have made them a great deal larger than they are in the fly, so that you can see them plainly." [Illustration: Saw of the Saw-fly, with Rasps shown in the Cross-lines.] [Illustration: Portion of the Saw-fly's comb-toothed Rasp, and Saw.] CONVERSATION II. _Uncle Philip tells the Children about Grasshoppers and Bees, that bore Holes with a Gimlet._ "Well, Uncle Philip, here we are again, to hear more about the tools that animals work with; we have seen in the bark of trees, and old wooden posts, little holes as round as a gimlet could make, and we have been thinking whether any of these little creatures have augers and gimlets, as well as saws. Do you know of any of them that can bore holes?" "Oh yes, boys; I know of more than one that can bore as smooth and round a hole as any carpenter you ever saw. There are some of the grasshoppers that have an excellent gimlet. The contrivance has five pieces in it; two of the pieces make a case to keep the augers in, two more are the augers or borers, and the other is a piece between the two borers on which they slide; this piece has a ridge on each side of it, and the augers have a groove which exactly fits the ridge. Besides this, each auger ends in a knob, and that knob has teeth all around it. Here is a picture of it." [Illustration: Ovipositors, with files, of the Grasshopper, magnified.] "But, Uncle Philip, what is the piece with the ridge for?" "Ah, boys, that piece shows the wisdom and the goodness of God. '_His tender mercies are over all his works_:' he has placed that piece there to keep the borers stiff, so that they cannot get out of joint, or be broken, when the little workman is boring." "Well, this is very curious."