284 The Joui'iial of Foreshy. 



25 ft., considerably more than any other silver fir that we are aware of, and 

 certainly one of the largest, if not the largest in Britain; 



In many parts of Scotland, in deep rich soils, and moderately sheltered 

 situations, silver firs are to be found ranging from 110 ft. to 120 ft. high ; 

 their weatherbeaten heads towering high above all other trees, and form- 

 ing a very marked and distinct feature in a wooded landscape ; and it is 

 said that they reach a still greater height in some parts of England and 

 Ireland than any we have mentioned, but of their dimensions we have not 

 yet seen any authentic particulars. A famous silver fir in Woburn Park, 

 Bedfordshire, is recorded to have grown for 110 years at the rate of one 

 foot in height per annum, and added to its contents at the rate of nearly 

 three and a half cubic feet annually. 



Insects Injurious to Trees. 



The large Red-belted Clearwing {S. culcifonnis) is a wood insect, the 

 moth depositing its eggs on birch stumps, though it will attack growing 

 trees : it is similar in habit to its brethren. Also red-banded as well 

 as red-tipj)ed is the Red-tipped Clearwing (5. formicceformis), not 

 uncommon near London amongst the osier beds on the upper Thames. 

 The moth is abroad at midsummer. The caterpillar lies hidden in the 

 pith of various species of Salis, liking best small twigs. Though it 

 has been reported as prolific enough to be injurious to the osiers in 

 some years, I have never heard of an authenticated instance of recent 

 date. In point of fact, none of the Clearwings are particularly 

 prolific, and one or two species have been less common than formerly. 

 Passing several rare and local species we come to the couple of Hornet 

 Clearwings {B. homhlciformis and a})iformis.) The latter, which is 

 the most frequent of the two, bears so close a resemblance to the hornet, 

 that each summer it alarms a number of nervous people; it is also 

 able to produce a humming sound. But it is quite harmless, nor does the 

 caterpillar do very material damage to the poplar, though it sometimes 

 attacks saplings, feeding unseen for nearly two years. 8. homhiciformis 

 in the larval condition resides within the branches of sallow or shoots 

 of the osier. 



In the family ZeuzeridcB there are only three British species, two of 

 these being important from the destructive effects they produce upon trees. 

 The large Goat Moth caterpillar {Zcuzcra cossus) is often to be seen ^at 

 the heart of some willow or poplar, which has on account of its un- 

 promising condition been doomed to the axe, i.iid occasionally at early 

 morn a caterpillar may be seen taking an excursion from one tree to 

 another. Despite its size, the Brown-winged Moth is seldom noticed, 

 though it rests on the trunks of trees in the daytime, for its colour 

 harmonizes with the grey or brown of the bark. Every female killed before 

 oviposition lias taken place is a gain in a park or plantation, as thereby 



