202 



NA TURA L HIS TOR Y. 



The form at the left of the cut is our common pea-weevil. The female 

 of this fastens her eggs to young pods of the pea just after the flower has 

 fallen. The larva which hatches from the egg bores its way into the 

 peas themselves, and grows with them, and after the peas are ripe it 

 changes to the perfect beetle. These 'buggy peas' are planted the next 

 war,°and then the beetle crawls out to lay its eggs as before. There are 

 various ways of averting the danger. One may keep his seed-peas two 

 years, and then they will germinate as well as ever, but the weevils will 

 crawl out of the peas the first year and die without finding a suitable 

 place to deposit their eggs. Or one may put the peas for a moment into 

 hoi water before planting them. This will not kill the germ, but every 

 weevil will succumb. 



Others of the weevils live between the bark and the wood of trees, and 

 frequently one will find their peculiarly ramifying mines in the bark of 



pine and other trees. A German 

 student has studied the habits of 

 these bark-weevils, and has made 

 some very interesting discoveries 

 in connection with them. The male 

 beetle excavates a copulation cham- 

 ber beneath the bark, and here 



awaits the females. After copula- 

 tion the females eat radiating pas- 

 sages out from this chamber, and on 

 the sides of each they lay their eggs. 

 If only one female comes to the 

 male, then but one radiating pas- 

 sage is made ; but if there are more 

 females, the number of passages is 



Fig. 192. 



•Mines of bark-boring beetle (Seolytus) 

 in pine bark. 



correspondingly increased. The larvse in their turn eat passages at right 

 angles to those made by their mothers, and in this way are produced the 

 curious markings shown in our cut. Each species of these 

 bark-beetles produces its own style of burrow, and the expe- 

 rienced entomologist can at once say what form has made the 

 mines. 



The weevils already mentioned have a short head ; but 

 fig. 103.— Bark- others have the head prolonged into a sometimes enormous 



borin°" b6Gtl6 



{Tomicus), en- snout, at the very extremity of which are the small jaws, 



while the antennae, as shown in the cut, take their origin 



from its sides. Of these forms there are many species each with its own 



peculiar habits. Some of them feed upon grain, some upon rice, some 



