Aiimial Report for 1911 of the Zoologist. 383 



Winter washing of the trunks of trees in the neighbourhood of 

 osier attacks would probably d<i something to reduce the 

 numbers of this pest. 



A very mysterious case of an insect attack on Douglas Fir 

 was reported from Herefordshire by Mr. Percy Rogers, agent 

 to Mr. Chas. Coltman Rogers, of Stanage Park, Radnorshire. 

 The firs had been planted in an open space in a wood, but in 

 close proximity to some hard wood and other trees, oak, 

 sycamore, hornbeam, mountain ash, scots pine and spruce, and 

 were from eight to twelve feet high. At the end of May the 

 tops became enveloped in web of caterpillars which were 

 feeding on the needles. The attack was almost over, and 

 the trees practically destroyed, when this information was 

 received, and there was little material to be obtained. In what 

 was sent, several caterpillars were found, but one — a geometer 

 caterpillar — was the most numerous, and apparently the chief 

 culprit. The specimens when they arrived were far from 

 lively, and the chance of breeding any of them out into moths 

 seemed slight. Specimens had also been sent to Kew and to 

 the Board of Agricultui-e, but no success has attended efforts 

 to obtain the mature insect, and the species remains unknown. 

 Tlte only geometer caterpillar which is known to feed on 

 conifers — except those of the winter moth group — is Fidonia 

 piniaria, but the caterpillars in question certainly did not 

 l)elong to that species. The presence of numerous "looper" 

 caterpillars spinning up the top of the fir-trees seems to be a 

 phenomenon which has not previously been recorded, and it 

 is very unfortunate that its identification was not possible. 

 Another interesting attack was reiiorted on hollies. With the 

 exception of the leaf-mining fiy Fhytoinyza ilicis, holly trees 

 are usually remarkably free from insect pests. In the case 

 under consideration the terminal shoots were being destroyed 

 by small caterpillars which spun the leaves together, and the 

 work seemed to be precisely that described by Gillanders as 

 due to a small Pcedisca moth. Some of the caterpillars 

 pupated and moths were obtained, but they proved not 

 to be Pcedisca, but Peronea hastiana, which appears to be 

 unknown as a holly pest. 



Corn and Grass Pests. 



There were inquiries after all the ordinary corn pests : — 

 Frit fly and tulip root in oats, gout fly in barley, wheat-bulb 

 fly and wheat midge in wheat, and " leather jacket " and 

 wireworm in various crops. The only case in this section 

 that was at all remarkable was the occurrence of the grubs 

 of the garden chafer, Phyllopertha liorticoJa, in pasture land. 

 The summer chafer, Rhisotrogvs solstitialis, is commonly 



