OUTSIDE AND IN. 



in 



with the flat part turned the other way, e. Surely this re- 

 minds you now of something you have seen ? Or must I draw 

 the something (Fig. 22) ? 



6. All grasses are thus constructed, and have their leaves 

 set thus, opposite, on the sides of their tubular stems, alter- 

 nately, as they ascend. But in most of them there is also a 

 peculiar construction, by which, at the base of the sheath, or 

 enclosing tube, each leaf articulates itself with the rest of the 

 stem at a ringed knot, or joint. 



Before examining these, remember there are mainly two 

 sorts of joints in the framework of the bodies of animals. 

 One is that in which the bone is thick at the joints and thin 

 between them, (see the bone of the next chicken leg you eat), 

 the other is that of animals that have shells or horny coats, in 

 which characteristically the shell is thin at the joints, and 

 thick between them (look at the next lobster's claw you can 

 see, without eating). You know, also, that though the crus- 

 taceous are titled only from their crusts, the name 'insect* 



