244 NATURAL HISTORT OP 



never fails to approach the mouth of its hole, that 

 there may be no obstacle to the development and 

 escape of the perfect beetle, which is of much larger 

 size than the larva, and not furnished with instru- 

 ments of equal efficiency for penetrating wood.* 



These insects lay a considerable number of eggs . 

 which they deposit in the crevices and fissures of 

 trees. They are of an oblong form, and usually of 

 a dirty -yellow colour. Those of some of the larger 

 species are nearly equal in size to the eggs of many 

 of the smaller birds. The following figure on the 

 left represents those of 

 P. giganteus; but as the 

 specimens from which 

 they are taken have 

 been long preserved, 

 they have no doubt shrunk considerably from their 

 original dimensions. 



Like the generality of insects that deposit their 

 eggs in holes and narrow fissures, into which the 

 extremity of the body could not readily be intro- 

 duced, the female Prioni are provided with an in- 

 strument which issues from the terminal segment 

 of the abdomen, and forms a canal along which the 

 egg slides in security to the place destined for its 

 reception. This instrument is of a horny consist- 

 ence, and generally bears a few small teeth or angu- 

 lar projections at the point on the outer side, which 



*Olivier's Entom. iv. p. 4. 



