231 



lobe ; the maxillary palpi arc well developed, and furnish characters 

 which are much used in classification ; the labium is usually well 

 developed, and bears three-jointed palpi. 



The females deposit their eggs in masses enveloped in a gelati- 

 nous covering. These are often found adhering to the end of the 

 body in captured specimens. It is supposed that these eggs are 

 usually deposited on aquatic plants ; but it is known that in some 

 case nales descend below the surface of the water to oviposit. 



The larva.' are long, cylindrical, soft-bodied, and furnished with 

 A ell-developed thoracic legs and a pair of anal legs. The abdo- 

 men bears a greater or less number of hair-like tiaclK-.il gills. These 

 larva? protect themselves by building a case about the body, in which 

 they live during the larval and pupal stages. These cases vary 

 greatly in form, and in the materials used in their construction; but 

 in general those made by the larvae of any given species are very 

 similar. 



One of the most interesting topics which a young cntomo! 

 can take for study is the habits of these insects. The larvaj can be 

 '.y found throughout our country. Many species can be kept in 

 aquaria; but others, those that live in swiftly-flowing water, must be 

 1 in their native haunts. I will indicate a few of the general 

 in the economy of these insects. The facts given here can 

 supplemented by any careful obser 



Among the simplest of the various forms of houses built by 



Cad. rms are those made by certain species that live under 



stones in rapid Breams. These consist merely of a few pebb'u - 



'. to the lower surface of a larger stmie by threads of silk. 



In the space 1>et\\een these stones the worm makes a more or less 



ect tube of silk, within which it lives, Very little respect for 



the tural skill of these builders is commanded by then rude 



Hut if one looks a little farther, something will be found 



imiration. The dweller within this nidi 

 nan; and stretched betueen t \\ " M >m s near by can 

 be seen his net. This is n ".ding in two 



to f,.nn m. 



It is as if a spider had mall \vel> in 



the cu: the swiftest. In the streams about 



Ithaca ' \ abundant. They occur in 



and in gieat. r nun 



alor : built upon the su; 



of the rock. ni-ellipti 



