SCALE-INSECTS. 
51 
Lecanium caprece. —This is an abundant and widely-distributed 
species throughout England. It is a rather general feeder, and 
so destructive that it has been known to kill large patches of 
a hawthorn hedge. It occurs at St. Albans. 
Asterolecanium variolosum. — This species is exclusively confined 
to the oak ( Quercus robur ), on which it has been found at St. Albans, 
King’s Langley, and Tring. It is very largely preyed upon by 
the blue-tit (Pams cceruleus). At Sydney, New South Wales, 
owing to the absence of the Paridae, it occurs in abnormal numbers 
on the oaks in the Botanic Gardens, causing the leaves to wither 
at the tips and the young shoots to die. 
Apterococcus fraxini. — As the name of this species implies, its 
food-plant is the ash (. Fraxinus excelsior ), on which it occurs 
exclusively. It has been observed at St. Albans, King’s Langley, 
and Tring, but is comparatively rare in these localities. The 
insects fix themselves in the cracks and crevices of the bark of 
the trees, giving preference to the trunks of young trees and the 
smaller branches of old ones. 
Cryptococcus fagi. —The name of this species also indicates its 
food-plant, the beech (Fagus silcatica ), to which it is exclusively 
confined. It is an abundant species, and one of the most destructive 
of our native coccids. Badly infested trees seldom recover. 
All the above species are probably indigenous. The following, 
which occur under glass, have been introduced with their food- 
plant, and therefore are not truly Hertfordshire species :— 
Aclerda japonica and Antonina socialis. —These two species were 
found living in company beneath the leaf-sheaths of a newly- 
imported bamboo (Arundinaria japonica ) at Broxbourne, and they 
are not known to occur elsewhere. Aclerda japonica causes the 
leaf-sheaths to swell out at the parts which cover the insect. 
Ceroplastes cistudiformis. —This occurs on an orchid (Chrysis 
bractescens ) at Tring Park, where it is cultivated on account of 
its beauty. It does not appear to increase in numbers or to injure 
the plant to any appreciable extent. It was originally discovered 
on an orchid at Harrow. 
Lecanium persicce .—This species occurs chiefly on peach, nectarine, 
and rose, rarely on the vine. In this country it is most abundant 
under glass. It has been observed at Tring Park. 
Mr. It. Newstead’s work, from which these particulars of the 
scale-insects which are known to occur in our county are taken, 
is comprised in two volumes, the first of which has been published, 
the second being in the press.* Upwards of eighty plates, most 
of which are coloured, illustrate it. His account of the life-history 
and habits of the various species is most interesting, and while 
the species in all their various stages are minutely described, the 
work is of practical value to the fruit-grower and horticulturist, 
who will find in it the most approved methods of prevention and 
remedy fully treated of, and will learn from it what are the natural 
* This was issued to the members of the Ray Society in October, 1903. 
