HOW TO KNOW THE INSECTS 



633 



THE DEATH'S-HEAD HAWK-xMOTH DURING WINTER. 



than in the atmosphere. Otherwise they 

 may pass the winter in the pupal or 

 chrysalis stage, burrowing amongst the 

 moist mud and sand on the banks of the 

 pond, but not actually in the water. 

 Furthermore, if the lar\-a has not com- 

 pleted its development on winter's 

 approach, the insect continues in that un- 

 developed state during the cold season, 

 remaining more or less dormant at the 

 bottom of the pond. 



The graceful Dragon-fly (illustrated 

 p. 131) likewise spends its winter as a 

 larva in the muddy depths of the pool, 

 the nymph or pupa leaving the water in 

 early summer and completing its final 

 development to the winged stage on the 

 stems of the water weeds. 



The Stag Beetle (p. 260) in winter is a 

 larva or gi"ub hidden within the trunk 

 of the tree on which it is working destruc- 

 tion, and on which it sometimes feeds for 

 four vears. Its winged stage is probably 

 the summer season. Like- 

 the Cockchafer Beetles (p. 

 spend two or three years in 

 state, but in this case carry 

 work beneath the 

 roots of growing 



confined to 



wise with 



216), which 



their larval 



on their destructive 



soil, feeding on the 



plants ; the final winter is spent in the 



pupa stage also below the soil, the perfect 



beetle appearing in the summer season. 



The Giant Sirex, or "Wood Wasp" 

 (p. 491), in its winter habits resembles 

 the Stag Beetle, living for several years 

 in its larval stage in the heart of a tree. 



Regarding the Frog-Hopper, or " Cuckoo 

 Spit " (p. 259), I am quite unable to sa}' 

 how this insect passes the winter. The 

 complete life-history of an English species 

 has not to my knowledge been yet investi- 



gated. Here, therefore, is an 

 opportunity for some reader 

 of The Nature Book to 

 attain scientific fame in a 

 novel field. 



From what I have written 

 here, it is very obvious that 

 the various insects have 

 quite different methods of 

 solving the great winter pro- 

 blem with which, in this 

 country, they have neces- 

 sarily to contend. Therefore, 

 the only way in which to 

 make sure of an insect's 

 quarters is by close observation 

 movements as the cold season 

 approaches. 



Finally we may consider the beautiful 

 Lace-wing Fly (Chrysopa vulgaris) shown 

 below. The winter state of this insect 

 was for some long time a puzzle that I 

 was unable to solve. Entomological works 

 seemed uniformly mute upon the point, 

 excepting one work which stated clearly 

 that the insect passed the \vinter in the 

 larval stage. However, late in the 

 autumn of 1905 I met with some larvae 



winter 

 of its 



THE LACE-WING FLY. 

 Below are shown three cocoons. 



