THE ENTOMOLOGIST. 249 



appearance of the latter, hence its untimely decay. If we 

 now take a longitudinal section of the swollen midrib, we 

 find that it contains a long cell, tenanted by one or several 

 reddish-yellow, footless, 14-jointed larvae of about a line 

 in length. Their food consists of the juices exuding from the 

 incrassated sides of their dwelling-place; hence, if we open 

 the latter whenever we please, we shall almost always find it 

 licked scrupulously dry, but strewn with the black excrements 

 of its inhabitants. In about three weeks the larvae are full- 

 fed, when they become obese and sluggish ; the irritation 

 their licking produced on the sides of their chamber therefore 

 ceases, the sap no longer flows steadily inward, but becomes 

 accumulated in the more or less pod-shaped, fleshy halves of 

 the gall ; a consolidation of the two halves respectively 

 ensues, and causes a longitudinal fissure between them on the 

 upper side of the midrib, through which natural opening the 

 larvae drop to the ground, in which they bury. Here they 

 shortly become sculptured pupae, exhibiting all the limbs of 

 the future fly, in thin semi-transparent sheaths, which are 

 laid flat along .the breast. In about three weeks from the 

 time of burying, the mature pupae force their way half out of 

 the ground, and the perfect midges, by bursting their silver- 

 white pupal skins, make their appearance. A few hours' 

 breathing give them the use of their wings and limbs. They 

 are two-winged Cecidomyiae, or gall-midges; and the species 

 has been described by Winnertz under the name of Ceci- 

 domyia botularia. In its living state it is about a line 

 in length ; it is reddish-yellow, with a white beak ; its thorax 

 shows three narrow, short, pale-brown streaks ; the poisers 

 are pedunculated and whitish ; in the segments the abdomen 

 is brown, each segment with a fine brownish lateral streak ; 

 the hind border of the segments, above and beneath, is 

 fringed with long whitish hairs. The six legs are long and 

 slender, brownish, and clothed with a white pubescence. 

 The wings are comparatively large, transparent, with sparse 

 grayish hairs, and suffused with a weak iridescent violet; 

 their viens are brownish. The feelers are brownish, 26-jointed 

 in the male, and 14-jointed in the female ; the latter is fur- 

 nished with a short ovipositor. The ravages of this midge are 

 mostly confined to the lower and protected limbs of the ash, 

 and if the underside of the branches is examined, a glance 



