XXXIV ANALYTICAL TABLE. 



A. Metathorax slightly prolonged under the post- 



scutel beyond it, being truncate before; 

 its concavity margined with sharp edges, 

 nearly angulate on each side 

 Abdomen slender, cylindrical ; first seg- 

 ment as wide as the second. Body vel- 

 vety . . . . . . .313 



B. Metathorax scarcely, or not distinctly pro- 



duced under the post-soutel, beyond it . 

 Abdomen elongate, cylindrical, with ihe 1st 

 segment as wide as the 2d, elongate ; or . 

 ovoid-elongate with the 1st segment a 

 little narrower, rounded . , . 313 

 * The 1st and 2d abdominal segments each 

 adorned with two yellow spots, or 

 fascia? beside their marginal fascia . 313 

 ** Only the second abdominal segment 

 adorned with two yellow spots which 

 are often wanting, principally in the 



males 321 



*** No free yellow spots on the first two 



abdominal segments . . . 327 



2. Form less cylindrical, not much elongated, the 

 thorax often short, and -wide anteriorly, 

 contracted posteriorly. Metathorax more 

 convex, rounded; its fossette generally 

 small, but always distinct. Abdomen ovoid 

 or irregular, the first segment narrower than 

 the second, not truncate anteriorly, not as 

 sessile; second segment more swelled than 

 in the preceding, short and convex, con- 

 tracted at base to fit into the first . . 332 

 A. Form rather stouter, abdomen rather wide in 

 the middle, but yet attenuated before. 

 The fossette of the posterior face of meta- 

 thorax rounded, always distinct . . 333 



a. Thorax but slightly adorned with yellow; 



(sometimes quite black, with a yellow 

 spot under the wine) ; post-scutel quite 

 black or adorned with two yellow dots . 333 



b. Anterior margin of prothorax adorned with 



yellow, but not the posterior margin ; 

 the yellow fascia offen bilobed or inter- 

 rupted. Fossette of metathorax large, 

 rather triangular, occupying nearly the 

 whole width of the metathorax . . 334 



