THE SOUTHERN PINE SAWYER. 



53 



transformations (ii^s. 19, c, 20). Tlic unliiiislHMl aim of the "U" is 

 usually oxtonclod by tho hiiva to witliin about one-quarter of an inch 

 of the surface of the wootl. Wlien the hii-va pu'Jjates, the liead of 

 the pupa is turned toward the end of the chaml)er. AMien the pupa 

 chanjxos to the a(hih. the beetle extenils tlie chamber to the surface of 

 the wood and tlirou<^h the bark, if tlie bark is still upon llie tree or 





FlO. 21.— The pine sawyer: Seolion oi pine showing, at right, nia.ss ot >x)rings and 

 refuse packed under bark (bark removed) by the larvsc and clianncls niadf 

 through the mass by tho larvip. a, Entranre hole of larva in woo(i; 6, scor<Hl sur- 

 fareofwood; r.pgg pit; rf.emercence hole, .\lxiut one-half natural size. (Oriplnal.) 



lop, !)orinp a ])erfectly round exit hole usually about three-ei;xliths of 

 an inch in diameter (figs. 19, 21, 22), tliereliy esca])ing to pro])a<4ate 

 tlie species in another tree or trees. 



NATURAL ENEMIES. 



.]fonohantnm.'< fiiilUitor is ])r(yed u])on by larva' of the coleo])tei<)Us 

 family Troj;:ositidir; by tlie larva of an elaterid beetle of the genus 

 Alans, and by a ."^pecies of Bracon which has been determined as new 

 to science. None of these, however, has been powerful enough, so 



