Correspondence 



323 



September and October. It was remarkably abundant in a 

 wood near Heyshott Down in October last. Finer specimens 

 we have never seen, some of the ascophores were nearly an 

 inch in diameter. 



Otidea auvantia, with us, always occurs on newly made roads. 

 Wherever a new road is made, this plant appears the next 

 autumn. 



Inocybe echinata. — We found it late in October in one of the 

 great beech woods around Heyshott Down. Massee wrote of 

 it, 1 " Probably an introduced species in Europe, never occur- 

 ring in woods, &c, but only in conservatories or botanical 

 gardens." 



CORRESPONDENCE. 



The Sirex gigas is one of the largest of our native hymenop- 

 terous insects. It is yellow and black, with a body about one inch and 

 a quarter long. The female, which is more frequently seen, has a long 

 stout ovipositor, which she uses to pierce the bark of trees and to 

 place her eggs in desirable positions. The possession of this auger 

 has gained her the popular name of " Horn-tail," but both sexes are 

 together usually termed " wood wasp," though the term is not a 

 correct one. The Sirex is more nearly related to the saw-flies than to 

 wasps. 



The Sirex is classed amongst our injurious insects. The eggs are 

 laid in Scots pine, spruce and silver fir, sometimes in felled trunks, 

 but more frequently in standing trees that are not in robust condition. 

 The fat white maggots feed in the solid timber. They are full grown 

 in about two months, when they form a silken cocoon at the end of 

 the burrow. The duration of the pupal state seems very uncertain, 

 in some cases it appears to be very lengthy, the perfect insect emerg- 

 ing from timber which had been built into houses a long time pre- 

 viously. Many instances of prolonged metamorphosis in insects are 

 on record : — 



Mr. Thomas Markham's interesting " Account of an Insect of the 

 Genus Bnprestis taken Alive out of Wood composing a Desk which 

 had been Made above Twenty Years," was read before the Linnean 



1 "Monograph of the Genus Inocybe, Karsten," Annals of Botany, July, 

 I904- 



