16 THE ENTOMOLOGIST. 



** Abdomen and legs partly red or reddish yellow. 



I Hind femora entirely red. 



§ Mesopleura in front with a vertical ridge. 

 X Lower margin of 3rd segment of abdomen concave. 



2ud and 3rd segments of abdomen with a brownish mark on the side. 



5. cuhrator, 8 lines. 

 X X Lower margin of 3rd segment not concave. 



Middle of abdomen red. . . - . obreptans, 4 lines. 

 §§ Mesopleura in front without a vertical ridge. 



Middle of abdomen red ; 3rd segment without a lateral black streak. 



juvenilis, Z\ — 4^ lines. 

 l\ Hind femora black, or partly black. 



Hind tibise black ; 3rd segment below not concave. 



-t- Abdomen red ; base and more or less of apex black ; between the 

 punctures of the mesopleura reticulate ; no vertical ridge behind 



front C0X8B. erythrog aster, 4^ lines. 



-t--i- Middle of abdomen red; between the punctures of the mesopleura 

 smooth, with a ridge behind front coxae (male), punctatus, 5 lines. 

 CO Hind tibiae not entirely black, more or less red or reddish yellow. 

 ■>■->■ Mesopleura between the punctures smooth. 



un Mesonotum between the punctures smooth, bucculentus, 5 — 6 lines. 

 unu^ Mesonotum between the punctures reticulate. 



' 3rd segment of abdomen more or less concave below. 



! Abdomen in the middle widely, and legs yellowish or testaceous ; 



coxae, hind trocbanters and base of femora black; mesopleura 



without a veitical line behind front coxae. 3. cannifrons,S — 10 lines. 



!! Middle of abdomen and part of legs red ; mesopleura with a vertical 



line behind front coxae. - - - 6. nitidulator, 6^ lines. 



" 3rd segment of abdomen not concave below (female), ruguhsus, 8 lines. 



^^^^ Mesopleura between the punctures reticulate; transverse anal 



nervure divided below the middle. 



* 3rd segment of abdomen more or less concave below ; forehead most 



frequently with an elevated ridge. 

 \ Mandibles and tegulae black ; aculeus of female long. 

 Middle of abdomen, greater part of front legs and middle of hind 

 tibiae red. ..... terehrator, 5 — 6 lines. 



If Mandibles pale ; aculeus not long. 



3rd, 4th, and sometimes 5th segments of abdomen red. 



1 Transverse anal nervure of hind wings divided just below the 



middle ; scutellum at sides marginated almost to the middle. 

 § 8rd, 4th, and 5th abdominal segments and part of legs red. 



2. pugillator, 5^ lines. 

 §§ 4th and 5th segments black. - - - unicinctus, 7 lines. 



II Transverse anal nervure divided almost at the bottom. 



Post petiole with three longitudinal oblong depressions ; middle of 

 abdomen and part of legs red. - . trisculptiis, 7 lines. 



** 3rd segment of abdomen not concave below. 



Mesopleura with a distinct vertical ridge behind the front coxae. 

 Fovea of antennae dilated above into a distinct ear-like process. 



Middle of abdomen red ; greater part of legs red. anceps, 5 — 5|- lines. 

 00 Fovea of antennae not dilated above. 



1. Forehead above the antennae furnished with several prominent 

 vertical ridges. 



