Iiisciis ON lihn ain/ II "illoii\ 1 1 5 



wasps iVotl loadily oil' the honey-tlew excreted l>y this species of 

 aphis, ami also thai hees totally disregarded il. The tlow of honey- 

 dew produced hy this species is very copious aud does much damage 

 to the tixHJS and those heneath. It is not at all unusual f<jr willows 

 and osiei-s to l)e killed outright hy it. 



Tlie efleet of the i)unctuivs of these plant lice is to leave distinct 

 brown scars in stripes. This ])lant louse is also known as the 

 Aphis saliijna, Walker, other synonyms being Aphis salicis, Curtis, 

 Aphis vimiualis, Boyer de yonscoloinbe, and Lachnus vimino/is, 

 Ta-sserine. The wingless viviparous female is dark yellowish-brown 

 to gix?yish-brown ; the antenniu red at the base, black at the tips, 

 and there are two dark spots on the thorax. The alnlomen is much 

 ix)un(kHl and in the centre is a curious horn-like projection ; the 

 cornicles are large and short ami there are five to six rows of large 

 black spots on it. The legs are deep brown, rather long and haiiy. 

 In length they are about O'lG of an inch. The pupa is much like 

 the larva, but rather longer and with bright brown wing cases, and 

 the doi-sixl tubercle is very large. 



Tlie winged female is quite a large insect, 4 to 5 mm. in length, of 

 a dull brown colour with darker marks, the abdomen being spotted 

 with Idack, one large spot placed centrally ; this spot apparently is 

 the representative of the tubercle seen in the wingless female ; the 

 short cornicles are almost conical. The long wings always seem to 

 Ije canied horizontally when the insect is at rest ; the stigma is long, 

 uaiTow and black; the in.sertion and cubitus orange-yellow. Tlie 

 le^'s are Ions, tln^ tibi;i> vollowish-rod, the two-iointed tai^si deei> 



As this is certainly a very harmful species steps should be taken 

 to destroy them by washing the willows with ])aratfin emulsion. 



Tliis sjKjcies is very common in some districts on willows and 

 »)siers. They congi-egate in mas.ses often half a foot in length and an 

 inch or more wide; they are usually grouix'd side by .side with their 

 heads jxunting downwards. When disiurl>ed these sedentary insoct.s 

 ln'come most active, yet do not leave their alKxle ; they throw their 

 long hind legs up and wave them about in an erratic manner, with 

 the probable intention of frightening ofl" the enemy, esi>ecially hymeu- 

 optei-ous pamsites. The elVect of this siMJcies on the trees is ver>' 

 strange. Some osiei-s ol)served this year were kille<l by them, whilst 

 others ch)se t4) only i»resente<l a yellow-leafed apiwamnce ; some she<l 

 their leav&s, others recovered in a few weeks. Cameren reconls a ca.s*> 

 where this Lachnus .swarme<l in such ntimbors at C'ai-shaltnn that 

 tnM\s thirty to fortv feet high had Kvn kilh-d by their jxiisonous 



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