THE YOUNG NATURALIST. 



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this kind of pattern in their devastation, that some of them are termed Typo- 

 graphers. It is scarcely possible to examine an ash tree, which is cut down 

 or damaged by lightning or storms, without finding traces of this insect. 

 Thousands of trees have been killed by this species. It is an almost invari- 

 able rule that the female may be found dead in the burrow in which it had 

 deposited its ova. Living trees, which have been attacked by this species, 

 are often attacked by Sinodendron cylindricum and Melandrya 

 carahoides, which complete the destruction. The latter species is very 

 variable in size (as are most wood feeders), it is blue or greenish-black and 

 shining. These insects feed in the decayed wood, also feeds on alder, birch, 

 willow, &c. 



Hylezinus vittatus a small species, is frequently found under the bark 

 of elm rails, it makes labyrinth-like passages in which the larva have fed. 



Scolytus ratzeburgi, this species is entirely black, it occurs in Scotland, 

 and feeds under the bark of birch. 



Scolytus destructor one of the most destructive insects to elm trees in 

 Britain, annually destroying many trees, and the injury is gradually spreading, 

 the beetles attack the trees by eating burrows in the bark, the females deposit 

 ova in the burrows, the larva make galleries at right angles from the burrows 

 of the females, and almost parallel to each other, under the bark. So great 

 is the fecundity of this insects that their countless numbers soon destroy the 

 largest trees. This species is abundant generally where elms abound, it is 

 stated to be very abundant in the neighbourhood of London, and its ravages 

 are so great as to endanger the growth of this tree. I believe this species 

 infested some large elms in Hyde Park which were spoke-shaved so as to 

 expose the larva. The above method succeeded, and the trees are recovering 

 from the above treatment, and the insects are destroyed. 



Scolytus pruni, this insect feeds under the bark of the plum tree, its 

 habits are similar to S. destructor, and no doubt the insect is abundant, 

 but orchards are not always accessable to the entomologist. I saw one tree 

 very much infested with it at Urmston, and one at Lindow, where, in passing 

 through a farm-yard, wherein was a quantity of felled trees and prunings, 

 portions of fruit trees, &c, on which I was using a bark knife, when the 

 owner of the material arrived, and after a little explanation he kindly directed 

 me to what had been a plum tree, which I found was very much infested 

 with these insects, I immediately inserted the bark knife under the bark and 

 was tearing some off, when a lady I had not previously seen, demanded to 

 know what the old plum tree had done to me, of course I apologised, and 

 she saw how matters stood, 



