OR, PLAIN TEACHING. 



369 



The larva of the chameleon fly, 

 16, is a very curious creature, 

 which may frequently be observed 

 rising to the surface 

 of the water to pre- 

 sent a beautiful star- 

 like apparatus, by 

 means of which it 

 breathes, to the air. 

 The head of the 

 chameleon larva is 

 small, and in this 

 respect easily dis- 

 tinguishable from 

 that of the gnat, 

 220. The insect 

 j ~ 03 - has also the power 

 by its star-like apparatus of 

 conveying down air for use under 

 water. This larva does not shed 

 its skin, but the proper state is 

 assumed within this covering, 

 which becomes hard and rigid. 

 In this state it floats upon the 

 surface of the water, the pupa 

 occupying one extremity of the 

 old envelope, out of which the 

 perfect insect escapes by making 

 a slit through the second seg- 

 ment. 



Among the smaller creatures 

 which people the waters in my- 

 riads, and which require the aid 



17 



1204. 



of magnifying glasses to clearly 

 discern them, are the cypris 

 orvata, or water fleas, 17. They 

 are beautiful objects for micro- 



1 



scopic examination, as, being semi- 

 transparent, their internal organi- 

 zation, with all its wonderful 

 workings, can be distinctly ob- 

 served. 



The apus productus, 18, or 

 water mite, is another of the 

 minute creatures requiring also 

 microscopic aid for satisfactory 

 examination. They often swarm 

 in myriads, and indeed, have been 

 known to be carried up by violent 

 storms of wind, and scattered 

 over the land ; hence they often 

 appear suddenly in puddles ot 

 rain water, where none have been 

 previously, especially in the spring 



1205. 



and early summer. They swim 

 well on the back, and when they 

 burrow in the sand they raise 

 their tails in the water. It is 

 said that they live by sucking 

 the bodies of tadpoles, though we 

 have seen them in millions in 

 pools where tadpoles were not to 

 be foufid. When first hatched, 

 they have only one eye, four oar- 

 like legs, with whorls of hairs ; 

 the body has then no tail, and 

 6* 



