igoj.] Insect, Fungous and Other Pests. 



163 



larvae of Sciara, a fly belonging to the family Mycetophilidce, or 

 fungus gnats . These larvae are frequently found under damp bark 

 or in decaying vegetable matter. It may be said that in general 

 they are not harmful to vegetation, but in habit are really 

 scavengers. One species, however, has proved harmful on mush- 

 rooms, and it has been necessary in some cases periodically to 

 fumigate houses and cellars and to destroy the flies that swarmed 

 on window panes or other places by spraying with paraffin 

 emulsion. 



Among other pests submitted for identification or advice as 

 to the best method of prevention and remedy, may be men- 

 tioned :— (1) Caterpillars of the magpie moth {Abraxas grossu- 

 lariata), an account of which will be found in Leaflet No. 20 ; 



(2) the millipede Julus pulchellus, described in Leaflet No. 94 ; 



(3) red spiders (see Leaflet No. 41) which were attacking goose- 

 berries at Northwood and at several places in Hereford- 

 shire ; (4) currant aphides (see Leaflet No. 68) ; (5) wireworms 

 attacking oats (Leaflet No. 10) ; (6) stem eelworm, fully 

 described in Leaflet No. 46 ; and (7) raspberry moth caterpillar 

 (Lampronia rubiella), which was doing serious damage near 

 Belper (Leaflet No. 14). 



Clover Mildew. — Some clover plants forwarded from Horsham, 

 believed to be attacked by a fungous disease, were found to 

 be suffering from clover mildew, caused by Peronospora 

 trifolioriim, De Bary. Summer spores are formed throughout 

 the season, these enabling the disease to spread with great 

 rapidity. In the autumn, winter spores are produced on the 

 dead leaves lying about, and these commence the disease the 

 following season. 



Ploughing before the winter spores are produced is the most 

 certain remedy. After the spores are formed in the autumn 

 ploughing is of no avail, as the buried spores retain their 

 vitality for some years and are certain to come to the surface 

 again sooner or later. The fungus is common on many legu- 

 minous weeds, and such should therefore be kept down. 



Diseased Fruit Trees. — Several cases of fungous diseases of 

 fruit trees have been brought to the notice of the Board. The 

 minute fungus Didymella applanata, Sacc, was found infesting 

 raspberry canes near Botley, the tissues being destroyed and the 

 whole plant dying. The best remedial measure that can be 



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