192 
fraxini although it is cited by various authors for that species in 
Central Europe. The occurrences of Scolytus pruni on cherry 
laurel-and of Xyleborus sazeseni on Catalpa are also unusual 
and are due to ae — flora present in the gardens affording 
a wide range of hos 
Another feature 2 the list is the small number of pine-dwelling 
species recorded. This is probably due to the early removal of 
trees that are not thriving and of all felled stems and broken 
branches. While this applies to the pine dwellers it is obviously 
not applicable to the hard-wood dwelling bark beetles, for many 
elms in particular support a number of Scolytus broods which 
readily increase under favourable conditions—a phenomenon that 
deserves to be recognised and studied by all interested in 
Arboriculture. 
A further interesting feature of the bark beetle conditions in 
Kew is the very important part played by the woodpeckers 
and tits in keeping these insects within bounds. Two species 
of woodpecker occur, the green and the lesser spotted wood- 
peckers, and of these the latter accounts for more than half of 
the bark beetle broods reared. The tits, blue tit, great tit and 
others, are chiefly enemies of the smaller bark beetles, especially 
the twig dwelling ss saa 
