Galls caused by the larvae, nymphs, and imagines of 

 Aphis atriplicis Linn. 



on 



the leaves of Atriplex angustifolia Sm. 



PLATE 101. 



Synonymy of Insect. 



Aphis clienopodii Schr., Kalt. 



Habitat of the Orache.— Abundant in Britain on the 

 sea-coasts as well as inland, on waste places very near 

 the sea. Springs up as a weed of cultivation almost 

 everywhere. 



The Gall is formed by the larvae and nymphs puncturing 

 the upper surface of the leaves, thereby causing the 

 blades to thicken and roll upwards and inwards in the 

 direction of their length until they meet. 



Colour.— Pale green. 



Average Dimensions of a Mature Specimen. 



Length, 40 mm.; girth, 18 mm. 

 May be sought during the months of June, July, August, 



and September. 

 The Growth is complete by the end of July. 

 The Typical Condition of the gall is multilarval and 



multinymphal. 

 ECDYSIS takes place in the gall. The imagines emerge during 



August. 



Atriplex patula is attacked by Aphis atriplicis with as much 

 frequency, and with the same swelling and curling of the leaves, 

 as is the species now under consideration. 



Although not a large plant, it is sturdy in growth, and 

 having numerous leaves unfolded from early spring until late 

 autumn, forms an excellent host for this aphis. 

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