SIPHOOORYNE XYLOSTEI. 25 



of tliis species,* to the effect that BlioiKdosvphumpastl- 

 naccce, Koch, is only a " sport " (Spiehirt) from the true 

 R. caprece of Fabr., or else from B. cicutce, Koch. He also 

 states that under a lens the corrugations and markings 

 are very similar. Passerini, on the other hand, puts 

 S. caprece into his new genus Siphocoryne, which does 

 not possess frontal tubercles. The last author also 

 notices that B. pastinacecB, Koch, wants the minute 

 horn over the tail to be seen in B. caprece. 



I consider the insects are quite distinct. They 

 differ in the relative size of their wings and the form 

 of their vertices, and they do not appear to feed on the 

 same plants. 



SiPHOCOEYNE XYLOSTEI, SchranJc. Plate XLIY. 



Aphis xylostei, Schr., Kalt., Walk. 

 Bhopalosiphuni xylostei, Koch. 

 Siphocoryne xylostei^ Pass. 



Apterous viviparous female. 



Inch. Millimetres. 



Size of body 0-065X0-030 1-64X0-76. 



Length of antennae 0*050 1*27. 



cornicles 0-019 0-25. 



Lono- oval. Head broad. Thorax and abdomen 

 widening till they become broadest just above the 

 cornicles. Bright green. Dorsum much domed and 

 marked by rings. Antennre green, tipped with black. 

 Cornicles black, expanded at their mouths. Cauda 

 rather long and yellow. Legs moderate. 



Pupa. 



Dull glaucous green. Head with two black marks 

 between the eyes. Abdomen with minute, black, 



* ' Die Koch Pflanzenlause,' p. 42. 



