164 INJUEIBS OF MARITIME PINE. 



committed in the pineries of the Sologne, and more especially in the 

 imperial domains, the forests of which have been under my direction 

 for some time. In the Grillaire, an imperial domain in the vicinity of 

 Motte-Beuvron, the lignivorous insects have carried out their ravages 

 in the middle of an immense forest of pines from twenty to twenty- 

 five years of age. The ravages had taken place simultaneously on 

 a great number of points which served as centres to lacunes in the 

 forest, the extent of which went on augmenting year by year in circular 

 zones concentric with the primal circle ; and in the radii of these 

 concentric circles the trees were more diseased in proportion to their 

 proximity to the centre. 



" At the centre the trees had fallen and strewed the ground with 

 heaps of their debris ; farther away they remained standing, but 

 dried up in all their parts ; finally, at the extreme points of the 

 circumference the leaves and the buds were beginning to get yellow, 

 which announced the invasion of the insects ; and the presence of these 

 it was not difficult to ascertain otherwise, on examining between the 

 wood and the bark, where the wood was literally ploughed up by 

 numerous galleries which the myriads of lignivorous insects had dug 

 and inhabited. In the middle of these gaps, where not a maritime 

 pine was left standing, there were to be seen here and there some 

 Scotch firs, pinus sylvestris, which, respected by the insects, mani- 

 fested an astonishing vigour alongside of the languishing condition of 

 the maritime pine. 



" This fact," says he, " corroborates the opinion of M. Perris, who 

 does not admit that lignivorous insects attack the trees in a healthy 

 state. I accept willingly this opinion, supported besides, as it is, 

 by numerous observations conscientiously made ; and I think, with 

 the distinguished entomologist of Mont-de-Marsan, that the pineries 

 of La Sologne would be spared by these insects if the pines found 

 themselves in circumstances more favourable to their develop- 

 ment. 



" In the Grillaire the circular lacunes ravaged by the insects pre- 

 sent often an area of several hectares. The entire forest would have 

 disappeared under the destructive action of these parasites if measures 

 had not been taken to exploit them at once, and to forward the pro- 

 duce to Paris. 



" It is noteworthy that there is found generally in the centre of 

 each lacune charcoal debris, which marks the site of an old charcoal 

 furnace. The pine is very sensible to the effects of fire and of smoke. 

 la the forest of Villette (Loiret) the maritime pines are dead, from 



