IDOLOCORIDJE. 369 



upon the disk ; remaining portion pitchy black, apex piceous ; disk 

 pale piceous, palest in the centre; Cuneus broadly yellow at the 

 base, apex and inner margin narrowly yellow ; Membrane blackish, 

 iridescent ; a narrow white streak extends from under the apex of 

 the cells and below the inner margin of the cuneus to the anterior 

 margin, and below the latter a large, triangular dark patch extends 

 to the apex ; inner marginal nerve black at the base ; cell-nerves 

 pitchy black, apex white. Legs yellow ; 3rd pair sometimes reddish- 

 yellow ; thighs at the base yellowish-white, on the upperside with a 

 brownish streak ; tibiae ; 3rd pair sometimes piceous at the apex ; 

 tarsi brown. 



Abdomen underneath brown or black. 



Length, 3| lines. 



The following variety of the ? is frequently met with : Pro- 

 notum yellow, callosities black. Elytra orange-yellow, somewhat 

 diaphanous ; Clavus ; between the nerve and the suture white ; 

 Corium ; anterior margin and a broad streak next the claval suture, 

 white ; Cuneus pale yellowish-white, margins orange-yellow ; Mem- 

 brane pale ; cell-nerves yellowish-white. 



Abdomen underneath brown, sides and apex more or less yellow. 



All the other characters as in the foregoing description. 



This is a very common species on birch trees, in June and 

 July., We have taken it at Darenth "Wood and other places in the 

 London district. 



Genus 2. SYSTELLONOTUS, Fieb. 

 Elongate, narrow. Elytra contracted before the middle. 



Head vertical in front, a little wider across the eyes than long ; 

 transversely oval, but posteriorly produced into a neck, and dis- 

 tinctly narrowed ; Crown flattish, slightly raised above the upper 

 margin of the eyes and deflected to the base of the clypeus ; Clypeus 

 convex ; base in a line with the anterior margin of the eyes ; apex 

 produced, and with the short antenniferous processes in a line with 

 the middle of the lower half of the eyes ; Face long, pointed ; cen- 

 tral lobe long, narrow, convex, prominent ; side lobes short, narrow, 

 somewhat parallel. Antennce almost as long as the body ; 1st joint 

 cylindrical, shorter than the head; 2nd somewhat stout, 3 times 

 longer than the 1st ; 4th frds the length of the 3rd. Eyes large, 



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