822 
Annual Report for 1899 of the Zoologist. 
Prevention . — Attention to the following points will lessen the 
probability of future infestation. 
1. Sow as early as possible. Late-sown barley suffers most from 
the fly. 
2. Where attack is feared, dress with guano and superphosphate 
at the time of sowing, or with nitrate of soda and salt when the braird 
is up. 
3. After infestation scarify or cultivate the stubble as soon as 
possible after harvest. 
4. Destroy chaff and screenings, and if the barley-straw in 
autumn seems full of the fly, use it at once for litter. 
5. Keep down self-sown corn, and be careful not to grow rye 
or winter barley in the neighbourhood of infested fields. These 
crops are subject to attack, and perpetuate the pest. 1 
Red Spider. 
Tetranychus telarius, Linn. 
This often-described and too familiar pest has been particularly 
busy during the past dry season, and has done much damage, 
especially in hop gardens. Even such insecticides as are effective 
against the mite itself are powerless to destroy its eggs, which are 
well protected with a chitinous covering, so that frequent washings 
are necessary to combat successive broods, and great expense is 
thereby incurred. 
Of the various washes used, those of which I have received the 
most favourable reports are “ Chiswick soap ” and the “ Stott ” 
insecticide known as “ Killmright.” 
A distinct improvement has been noticed upon hops treated with 
the former compound. Of the latter, Mr. Duncombe-Eden’s bailiff 
at Cheveney Farm, Hunton, reports that it was “ much the most 
effective of the washes tried for red spider,” but he considered it 
too expensive for general use. Good results were also obtained by 
Mr. McDougal’s w r ash. 
A curious case of the infestation of a house with “ red spider ” 
was reported from Leamington. The windows, the brickwork, and 
the red sandstone string courses of a newly built house were 
swarming with these creatures, which were kept in check with the 
greatest difficulty. A sulphur wash was recommended, and the 
form in which it was applied was that suggested by Miss Ormerod. 
Four ounces of sulphuret of lime are well mixed with two ounces 
of soft soap, and a gallon of hot water added, and the mixture is 
1 la the middle of September last one of the rooms in the Physiological 
Laboratory at Cambridge was suddenly visited with a plague of innumerable 
small flies which, on examination, proved to be Chlorops tamiopus. None of 
the flies were to be found in the adjoining rooms. It was impossible to 
account for their appearance, certainly in hundreds of thousands, by any 
introduction into the room of infested straw. It can only be conjectured that 
they entered the room in a swarm through an open window. 
