IN THE PARKS OF LONDON. 47 



less decisive measures were soon taken to resist the progress of 

 the contagion, it was to be expected that not only every tree 

 of this species in the Parks would be destroyed, but that the 

 evil would be disseminated throughout the vicinity of the me- 

 tropolis, to several plantations on the north of which it had 

 already extended. 



In this state of things, Mr. William Sharpe Macleay, an 

 eminent Naturalist, profoundly acquainted with the history 

 of Insects, was requested by Lord Sidney, the Ranger of the 

 Parks, to draw up a report on the state of the Elm-trees in 

 them, for the purpose of referring it to the Lords of the 

 Treasury. 



In this Report Mr. Macleay shows that all the havoc had been 

 committed by a species of Beetle belonging to the same natural 

 family as that which destroyed the Pines in Germany ; and 

 not more than one-sixth of an inch in length ; called the Hy- 

 lesinus Destructor, or Destroyer Hylesinus*. 



It appears further from the Report, and from other authentic 

 sources, that from the end of March to September, but princi- 

 pally about the end of May and the commencement of June, 

 this insect, distinguished by its polished black head and tho- 

 rax, the head thickly covered with hair, and its brown wing- 

 cases, may be seen, in numbers, running over the trunks of the 

 Elms. This is the animal in its perfect state. It may be 

 seen also entering into holes, with which the bark appears per- 

 forated as though with a gimlet; it insinuates itself into these 

 holes, or into the crevices of the bark, for the purpose of de- 

 positing its eggs. On stripping off a piece of the loose bark, 

 we may easily at any season understand how the barking of 

 trees is effected by these minute animals; for the surface of the 

 wood thus exposed presents to the view innumerable impres- 

 sions, or excavations, each consisting of a comparatively wide 

 middle trench, with others much narrower, extending from 

 it at right angles, but in a parallel direction to each other f. 



* Has not the ingenious author of " Insect Architecture," in the Library 

 of Entertaining Knowledge, confounded this insect with the Bostrichus Ty- 

 pographus (Tomicus Typographus, LATR.) where (p. 239) he reports the latter 

 to have been found in the neighbourhood of London ? 



f Mr. Macleay has accurately compared these impressions to impres- 

 sions or casts of large and broad Scolopendrae, the insects commonly called 

 centipedes, or hundred-legged worms. The details above given on the history 

 of the timber-eating insects, formed part of the Public Lecture delivered at 

 Hazelwood, and were illustrated by a transparency representing, on a much 

 enlarged scale, the magnified figure of the Scolytus (Hyksinus) Destructor, 

 given in Mr. Curtis's British Entomology (Vol. i. Plate 43.), with a plan, 

 also enlarged from a figure in the same work, of the impressions made by 

 the insects, and another drawing showing these impressions in section, as 

 they would be exposed by a rertical section through the diameter of an in- 

 fected trunk. 



