HYMENOPTERA. 401 
perforation by insects of leaden balls contained in cartridges 
prepared for war. M. Milne Edwards read to the Académie des 
Sciences a short Report on these works. 
The insect which had produced the perforations observed in the 
balls sent to the Crimea in 1857, and which M. Dumeril par- 
ticularly studied, was the Sirex juvencus, and had been taken from 
France in the wood forming the boxes which contained the 
cartridges. In the other case of which we are speaking, that is 
to say, of the cartridges which were sent in 1861 to the Académie 
by Captain Heriot and by M. Bouteille, the perforations had been 
produced by another species. M. Milne Edwards, who found the 
insect that had caused this strange damage, had no trouble in 
recognising it as the Sirex gigas, which, in its larva state, lives 
in the interior of old trees or pieces of wood, and which after it 
has gone through all its metamorphoses, comes out of its retreat, 
to reproduce its kind. To clear themselves a way, they cut away 
with their mandibles the ligneous substances or other hard bodies 
they meet with on their road. It was in pursuing this object that 
the insects, imprisoned accidentally in the packets of cartridges 
when they were yet only in the larva state, must have attacked 
the leaden balls, as also the paper and the other matters which 
they met with on their road, and which opposed their passage. 
M. Bouteille proves, in his Memoir, that 
M. Dumeril has committed an error in 
saying that the perforating organ em- 
-ployed by the Srrex to attack the leaden 
balls in the cartridges in the Crimea was 
the auger situated at the extremity of the 
abdomen of the female, and intended for 
cutting into that part of the wood where 
it is to lay its eggs. M. Bouteille has 
established, in fact, that they were not 
only the females which attacked the car- 
tridges, but that the males, which have no ~ gig, 379Tarva of a Saw Fly. 
auger, had occasioned the same damage. aera: 
The Tenthredineté are called ‘‘ Saw-Flies,” because the females 
are furnished with a double auger, notched like a saw, with 
which they cut into the branches in which they lay their eggs. 
DD 

