29 



and burning the bark, kc. ; but as I suspect that it is the want of ilying timber 

 which forces them to attack living trees, I would suggest that placing fresh logs, 

 during the spring months, in the neighbourhood of affected trees, as traps, and 

 destroying the beetles which come to them, woiild be more effectual. 



Eylesinus crenatus, which is also an ash feeder, is larger than HyUsinus 

 Fraxini, three to four lines in length, and proportionately a stouter insect, 

 giving it a more rounded and less cylindrical appearance ; entirely black ; some 

 fine ferruginous hairs on the tibise and head ; thorax minutely pitted ; elyti-a 

 with eleven rows of smaU tubercles, which give a rough appearance to the beetle. 

 Though widely distributed and abundant when it does occur, like the Xylophaga 

 it seems to be anything but generally common. I have found one tree which 

 owed its faU to its operations. The beetle had obviously been in possession 

 many years ; it had commenced the attack near the foot of the tree, on one 

 side the bark was destroyed by it round more than haK the circumference of 

 the tree, and to a height of 15 or 20 feet, the limbs above being dead, A zone 

 surrounding this contained the insect in all its stages, the remainder was still 

 unattacked. The portion of bark longest destroyed had fallen away, and the 

 wood beneath was in possession of Sinodendron Cylindricum and Doirus 

 paraUelopipedus, and was rapidly rotting. The tree was blown over in one of 

 the gales of last winter. I have also found Hyhsinus crenatus sparingly in several 

 other trees, all pollarded or otherwise sickly. Unlike H. Fraxini, H. Crenatus 

 takes two years to undergo its transformations, the larvre assuming the pupal state 

 at the end of the second summer, so that at present full-grown lart'te and perfect 

 beetles are both to be met with. Felled timber would be unable to support this 

 long larval existence, HyUiinus crenatus accordingly is never met with except 

 in living trees, and while an affected tree continues alive I believe that none of 

 the beetles desert it for another. They economise it as much as possible, the 

 destroyed bark being more completely riddled and devoured by them than by any 

 other beetle of the family I am acquainted with ; the burrows of the larvje are 

 much more irregular also, so that it is impossible to find one of those perfect maps 

 of their voyages (as in Hylesinus Fraxini) which have secured for these beetles 

 as a family the name of "typographers." Last winter the blown down tree I 

 have mentioned contained hundreds of the perfect insect ready to emerge on the 

 approach of spring, and but for the fall of the tree would have made their 

 bunows in it again, but now they have all left it, so that last week I had 

 difficulty in finding a specimen, H. Fraxini, of which odd specimens only were to 

 be found during the winter, now on the contrary abounds in it. The parent 

 galleries of H. crenatus are proportionally much shorter than those of H. 

 Fraxini, and more frequently consist of only one branch, the male and female 

 both enter the burrow as with H. Fraxini, but the male usually leaves before the 

 gaUery is quite completed. The eggs are fewer than with Fraxini, and laid in 

 a deeper cavity, and so thickly covered with a layer of frass as to require 

 looking for. 



