DRYOBIUS ROBOEIS. 71 



N.B. — It may be noted that in some Aphides the 

 rostrum attains its full development and length at the 

 early stages of life. There seems afterwards to be an 

 arrest of growth. In some genera to follow, this organ 

 in the young projects far beyond the end of their bodies, 

 whilst in the mature forms the proboscis hardly attains 

 to the third coxa. 



Detobius eoboeis, Linn. Plate CIII. 



Aphis roboris, Linn., Fonsc. 

 Lachnus fasciatus, Burm (?). 

 Cmara rohoris, Curtis, Sir 0. Mosley. 

 Lachius Qvhoris, Kalt. 

 DryapMs, Amyot^. 

 Dryobius roboris^ Koch. 



Apterous oviparous female. 



Indies. Millimetres. 



Size of body 0-150 X 0*090 3-81 x 2'27. 



Length of antennge 0-070 1-77. 



cornicles 0-010 0-25. 



S9 



5> 



rostrum 0*060 1*52. 



Oval, anterior portion produced. Head and thoracic 

 segments narrow. Abdomen broad across the cor- 

 nicles. Colour shining reddish brown. Head, thorax, 

 and last abdominal ring blotched with black. Cor- 

 nicles very small, dark, and rising from circular black 

 patches from the sixth abdominal segment. Antennae 

 slender, orange-brown with black tips. Legs shining- 

 orange with black tarsi, and black femoral and tibial 

 points; tarsi with two distinct joints; hind legs very 

 long. Rostrum reaches beyond the third coxee. 



Apterous pviparous female. 



This has very much the appearance of the last 

 insect. Koch says it much resembles the female of 



