EUROPEAN OR FIELD ELM. 495 



all 'iiave vanished. The larvae are small and slender, and devour the leaves 

 with equal avidity as the perfect insect. Somctinies small bladders or galls are 

 produced on the leaves of the elm, by the puncture of some kind of insect, (pro- 

 bably a cynips,) which are at first green, but afterwards turn black. Each of 

 these galls contain a flnid, which, according to Du Hamel, is called elm balm, 

 dnd was formerly employed for the cure of recent wounds. 



In the " Nouveau Cours d' Agriculture," there are mentioned four other insects 

 that prey upon the elm. The first is the larva of the Bombyx chrysorrhoea, of 

 Fabricius, wljich destroys the leaf-buds and leaves entirely, so as to give the 

 tree, in spring, the appearance of winter. The second is the Galeruca iilmar'ian- 

 sis, of Fabricius, a coleopterous insect, the larvae of which, in some seasons, 

 entirely destroy the parenchyma of the leaves of the elms, in the public prome- 

 nades both in [Britain and in continental Kurope. These larvae are of a blackish 

 colour, and exhale, when crushed, a most disagreeable odour. The moment 

 they are touched, they coil up, and sufier themselves to fall to the ground. The 

 perfect insect is extremely sluggish in its movements, feigning death, in cases 

 of danger, rather than unfolding its wings to fly away. It conceals itself in the 

 crevices of the bark, also under stones, and between the bricks of walls; and 

 sometimes will produce three generations in the course of one summer. The 

 third is a species of goat-moth, {Cossus Ugnipcrda^ of Fabricius,) the larva of 

 which is about three inches long, with its body sprinkled with slender hairs; 

 being of a reddish- brown on the back, becoming yellow beneath, with eight 

 breathing-holes on the sides, and a black head. It exhales a most disagreeable 

 goat-like odour, which is produced by an oily and very acrid liquor, that it dis- 

 charges at its mouth, and the use of which is supposed to soften the wood before 

 it devours it. The pupa is brown, the abdominal segments bearing two rows 

 of spines, directed backwards. Before entering into its chrysalis state, which 

 sometimes takes place under ground, the larva spins a strong web, intermixed 

 with particles of wood, that constitutes its cocoon. The perfect insect has dark- 

 gray wings, clouded with dark-brown, and streaked with black. It belongs to 

 that class of insects which fly by night, and appears, in Europe, in the month of 

 June. The female lays but one set of eggs, but these generally amount to one 

 thousand in number, and are always deposited at the base of the trees, whence 

 the larvae penetrate the bark, wherever they can find the easiest entrance. The 

 eggs are small, in proportion to the size of the imago; and the caterpillar, which 

 grows to a large size, is said to remain in the larva state three years. This 

 insect, in Europe, not only feeds upon the elm, but also preys upon the alder, the 

 oak, the ash, the walnut, the beech, the lime, and on some kinds of the willow, 

 and of the poplar. The larvae devour the liber or inner bark, making long gal- 

 leries in the wood, somewhat after the manner of those of the wood leopard 

 moth, (Zeuzera aesculi,) in the common pear-tree, and finally destroying the 

 tree. Many remedies have been proposed, but that of I.atreille appears to be 

 most approved of in France. This consists in surrounding the base of the tree, 

 where it has been observed that the females always deposit their eggs, witli a 

 thick coating of a mixture of clay and cow-dung, which the insect caiuiot pene- 

 trate. The green woodpecker preys upon these caterpillars, and its stomach, on 

 dissection, emits an intolerable stench. The fourth enemy to the elm, and the 

 one which is considered by far the most injurious, is the larva of the Sro/i/f/is 

 destniclor ; but it is sometimes assisted in its ravages by that of the Srolytus 

 ainmtus. In about the month of Jime or July, the female insect bores through 

 the bark, until she has reached the point between the soft wood and the inner 

 bark; she then forms in the latter a vertical channel, usually upwards, of about 

 two inches in length, on each side of which she dejiosits her eg<:s. as sh, 

 advances, to the number of from twenty to fifty in all. Jt appears probable that, 



