50 HYMENOPTERA. 



finger to the bone. The largest of the genus 

 is the Sirex Gigas, which often exceeds the 

 size of the one represented in pi. 54. It is 

 chiefly among cone bearing-trees, and has a 

 very conspicuous sting, or terminal tube. With 

 this sting the female perforates the fir-trees, and 

 deposits her eggs in clusters, sometimes to the 

 number of two or three hundred. The larva 

 is above one inch long, and not unlike a yellow 

 grub in appearance, but has a short black spine 

 at the end of the abdomen. It feeds in the 

 body of the tree, changes to a chrysalis in July, 

 and in three weeks time becomes a winged in- 

 sect. Some of them change late in the season, 

 and remaining all the winter shut up, emerge 

 from their case the following spring. 



SPECIFICATION. 



Sirex Gigas. S. abdomine ferrugineo; segmentis 

 3, 4, 5, 6, nigris, thorace villoso. Linn. Syst. Nat. 

 1. p. 928. Gmel. p. 2671. Fair. Spec. Ins. 1. 

 p. 418. Mant. Ins. 1. p. 257. Entom. Syst. 2. 

 p. 124. 

 Boesel. Ins. 2. Vesp. t, 8, 9. 





