Insects, etc., Injtirious to the Pear. 347 



are white to yellowish- white, and 'are composed of fourteen segments ; 

 the head is brownish, and bears two minute, two-jointed, nipple-like 

 antenmc ; the " anchor process " is long and brown, broadly expanded 

 at the free end with a median notch. 



They leave the fruitlets by a crack which develops in them, as a 

 rule leaping from the side to the ground below, where they still 

 exhibit those curious jumping movements common to this genus of 

 midges. Soon they work their way just under the soil. 



At first the young larva; form small tunnels in the fruitlets, some- 

 times these are dark, at others they can scarcely be detected with a 

 lens ; by degrees as they grow they eat out the pulp, and, as their 

 " frass " cannot escape, the whole of the inside of the pear becomes a 

 blackened mass. 



The depth to which they burrow depends upon circumstances. 

 Lintner (11) found them up to 2^ inches, but none below. I have not 

 yet found them below 1^ inch. They then form a delicate cocoon 

 in which they remain and pupate from October on into the M'inter. 



Those which remain enclosed in the fallen pearlets remain as 

 larviB until they can escape. 



Natural Enemies. 



J have been unable to find any natural enemies in this country. 

 KoUar, quoting Schmidberger (9), mentions a parasite Diplmpis 

 nirjricornis, Fabricius, as laying an egg in each larva. There are 

 no records of it, however, in this country. Marchal (23) records 

 Mostemma pyricola, Kief., with its quaint larva as attacking this pest. 



Prevention. 



At present we know of no plan which is generally adopted to 

 check the great increase of this pest. In a garden the matter is easy, 

 and even where we have only bush fruit, but where large trees are 

 attacked and over a wide area, nothing much seems of avail. 



In garden and on bush trees all infested fruitlets should be hand- 

 picked and burnt before the larvaj escape ; if this is persisted in for a 

 year or two over a good area the pest can soon be stamped out, but 

 unless it is done collectively by gardeners and growers the benefit 

 can be but of limited duration, for there is no doubt the insects can 

 fly some distance. 



It is even desirable to ruin all one's possible crop for a year to 

 stamp this pest out. This may be done by spraying heavily with an 



