16 



METHODS OF INSECT LIFE. 



things, as in the case of the well-known Colorado 

 Beetle (Fig. 14), on amount of cold and on height 

 above sea-level. Also in the fact of the hordes of 

 insects, which fairly sweep all before them on the 

 great continents, being suited for the climates where 

 they are found, but not for the constant change of our 

 island weather, we have a good reason for not fearing 

 their attack. 



Pig. U.- 



-1 and 2, Colorado Beetle, magnified and natural size ; 

 3, caterpillar ; 4, eggs. 



The shelters ivhich caterpillars and f/nibs of various- 

 kinds make for themselves to turn to the chrysalis in, 

 or to secure themselves in during Avinter, are of many 

 kinds. Some caterpillars, like those of the Silkworm, 

 have then the power of secreting a gummy fluid, and 

 by means of drawing this from their mouths they can 

 spin silken cocoons, within which they slip, or rather 

 shuffle, ofi' their old caterpillar-skin, and turn to chry- 

 salids ; others (as some of the common White Cabbage- 

 caterpillars) hang themselves up by a strong spun 

 thread passed round them, which acts as a band to 

 keep them from falling ; and many of tbe crop-feeding 

 kinds simjily hollow a cell in the ground, in which 

 they lie protected from moisture and sudden changes 

 of temperature ; many Fly maggots contract, and as. 



