20 PBACTICAL ZOOLOGY. 



7. When the larvae are ready to transform, they crawl 

 up out of the water, their skins split along the back, 

 and the adult dragon-fly escapes, leaving its dry, 

 empty skin, which may be found clinging to the stems 

 of water plants, projecting logs, or rocks. 



8. Draw a dorsal view. 



9. The dragon-fly belongs to the order Neuroptera, or 

 nerve-winged insects. 



REVIEW OF INSECTS. 



Take any insect not yet studied, and examine it thor- 

 oughly. Write a full description, and make drawings of 

 it. To which of the insects previously studied is this 

 most like? To what order, then, does it probably belong? 



Select two pages in your note-book that face each other. 

 On the left-hand page make a list of characters common 

 to all the insects you have studied, numbering the points ; 

 on the right-hand page write briefly the characters peculiar 

 to each insect. The first list ought to be a very nearly 

 correct definition of an insect, so far as external features 

 are concerned. The second list should serve as a defini- 

 tion of each of the orders of insects. 



All the orders of insects belong to the class Insecta. 



Write now a list, in vertical series, of the orders of in- 

 sects studied, with the name of the insect representing 

 that order opposite it, and include all within a brace oppo- 

 site the word Insecta. 



Read Hyatt's "Insects" (No. VIII. in Guides for Science- 

 teaching). See also " Standard Natural History," Vol. II., 

 and Saunders' " Insects Injurious to Fruits." 



