202 populus. 



taking fire, and even when ignited burning without flame 

 or violence. 



As an ornamental tree it well deserves a place in ex- 

 tensive grounds, its spiry height and pyramidal form before 

 it becomes aged, being well calculated to break long hori- 

 zontal lines, or the monotonous effect of round-headed trees ; 

 it also, in a great measure from its semifastigiate growth 

 in the young state, supplies the place of the Lombardy 

 Poplar in such scenery, either of wooded landscape or 

 in combination with buildings, as is improved by the pre- 

 sence of that tree. The principal objection to its frequent 

 introduction in ornamental scenery is the late period of 

 its coming into leaf, and the comparatively early one at 

 which the foliage is shed ; in the north of England it is 

 seldom in full leaf before the middle of June, and is again 

 denuded by the end of October. 



The caterpillars of Cerura vinula and Cer. furcula, as 

 well as that of Smerinthus populi, feed upon this Poplar. 

 We have also found those of several of the notodontidse, 

 that of Calyptra libatrix, and also the larva of a large 

 tenthredinous fly ; the stem of young trees is also subject 

 to the attack of Cryptorynchus lapathi, and in some seasons 

 we have had several plants completely drilled by the larva 

 of this weevil. 



In addition to the trees particularized in the " Arbore- 

 tum Britannicum," one of the largest and finest, and perhaps, 

 also, one of the oldest specimens of the species in Britain, 

 is now growing at Maxwell heugh, near Kelso. The trunk, 

 previous to dividing into the enormous limbs which form 

 the head, is sixteen feet and a half in height ; at the base it 

 measures thirty-one feet in girth, at two feet above the 

 ground twenty-one feet, and at ten feet above the base 

 eighteen feet ; its solid contents are found to be upwards 



