5996 



Enlomological Society. 



Curator, to assist me in bringiu"^ conclusive evidence before you that we are now per- 

 fectly acquainted with the true habits of the Scolytus destructor, and the means of 

 arresting; its future progress ; it is most peculiarly fitting now that Science should step 

 in and prove that over one pest at least we have power, and if not made use of the fault 

 lies entirely with the public. 



" Among the various pests that are constantly claiming attention by their 

 obnoxious powers, the Scolytus destructor holds no mean rank: the elm is one 

 of the most useful trees we have in this country ; it suits our climate, is extremely 

 ornamental and flourishes where others would not thrive so well, its timber is made 

 use of in various ways, and therefore its preservation is alike advantageous to our 

 ornamental paiks aud woodland scenery. Previous to 1840 the Scolytus destructor 

 was known, but its habits not perfectly understood : it was during the formation of the 

 Royal Botanic Gardens that my attention was first directed to the sickly state of the 

 elms forming the belt of the inner circle of the Regent's Park ; the axe was constantly 

 being applied, and large and increasing gaps pointed to where the trees had stood 

 and where destruction was going on : on enquiring of the parties laying out the 

 grounds as to the cause of the premature decay of these fine young trees, I was 

 informed that ' some had perished by having an inner embankment formed to prevent 

 parties outside the garden from looking over, and consequently a portion of earth had 

 been raised round their stems, and that others had died, and were dying from their 

 roots entering the gravel.' Now, if this latter information were true, I could not 

 understand why the circle of trees, separated by only a few yards from them, and 

 forming the next circle, were healthy, all being of the same age. In all cases where 

 the destruction was going on I found the Scolytus in great profusion: on mentioning 

 this circumstance to the Curator, the old stereotyped answer came in due form, ' that 

 this beetle always attacked sickly and deceased elms, and were since to be found in all 

 places where this timber had fallen or had been conveyed, either decaying along the 

 road-side or drawn into the timber-yard.' Now, in the first place, I was not satisfied 

 in my own mind that the trees were perishing from the assigned causes; the coinci- 

 dence was too remarkable not to be noticed, and I felt sure that there was something 

 more than the embanking and gravel to account for the rapid death of so many young 

 trees in diff'erent parts of the belt, more especially as my attention had been called, in 

 1842, to the state of the trees in St. James' Park; with a very little reflection I felt 

 convinced that insects had something at least to do with the matter, and that among 

 them, if the Scolytus destructor were not the first and absolute cause, their presence 

 acted most injuriously by still more disabling the already impeded circulation of the 

 sap: being fully impressed, after further close and most attentive examination into 

 the subject, of their powerful influence, I made it my business to study their habits, 

 and soon became so far master of them that I was induced, in 1843, to read a paper 

 upon the subject before the Royal Botanic Society, and detailed a mode of treatment 

 I felt almost certain would succeed : as the trees in the park belong to Her Majesty's 

 Woods and Forests, the Council of the Society applied for permission to allow me to 

 experiment upon some, and a row of eighteen, fairly selected, were placed at my 

 disposal. 



" The following eighteen trees were granted by the Commissioners of Woods and 

 Foiesls in 1843 



