832 fLUM. 



other borings were taken straight up and down the stem ; 

 these might be certainly as many as four (perhaps more in one 

 stem), and were from half an inch to upwards of an inch and 

 a half long, and of these tunnels (in the pieces of stem I 

 examined), one ran along the pith, which was completely 

 cleared away. The great injury caused by these galleries 

 fully accounted for the death of the stem. 



At the time of examination, that is, on or about September 

 12th, the tunnels were filled with beetles ; where the width 

 only was enough for one, the beetles were arranged in a row 

 one after another in procession, as it were ; where the tunnel 

 was a little wider (as where the pith had been cleared away), 

 they were less regularly arranged, but crowded in, so that 

 there scarcely seemed to be room for another. In one length 

 of wood of about two inches I found, as near as might be, 

 thirty beetles. The work of destruction was still evidently 

 going on, for in some instances I found that, instead of being 

 as usual black and discoloured, the sides of the tunnel or the 

 extremity were white and moist, showing the beetles were still 

 feeding. The instinct of tunnelHng was so strong at the time, 

 that a quantity of beetles which I secured in a tube buried 

 themselves so rapidly in the cork, that between the 10th of 

 September and the morning of the 12th they had already 

 bored five tunnels into it, and it contained at least seven 

 female beetles. 



A great peculiarity of this attack has been considered to be 

 the extreme rarity of males compared to the number of females, 

 and amongst from about fifty to sixty of these Shot-borers 

 which I took out of their borings in Plum stems in September, 

 I found only one male. Subsequent search, however, made 

 me think that in winter the difference in proportion of 

 numbers would be found to be not nearly so great, for amongst 

 some specimens I examined early in December I found a 

 larger proportion of males, and about a month later, amongst 

 specimens I took (on or about January lOtli) from a piece of 

 Plum stem two inches and a quarter across, about seventeen 

 males to six females. 



The borings at this winter time of year only contained a 

 sprinkling of beetles, instead of, as in September, being so 

 crowded up that there was scarcely room to insert another 

 beetle into the row that filled each boring. 



The method of attack is stated, by the well known German 

 observer Schmidberger, to be for the beetles to choose a spot, 

 usually on the main stem of the tree, making no distinction 

 as to the tree being sickly or healthy, young or old, so long as 

 it is thick enough for the purpose, — at least half an inch in 

 diameter. (The attacked stems sent me from Toddington were 



