FIELD BOOK OF INSECTS. 



No distinct spine on the outer angle of the obliquely- 

 cut apex 12. 



12. Black or brown; yellowish or whitish pubescence 

 arranged to form variable markings; usually four such 

 markings on the pronotum, and three bands (the front 

 one narrow and curved) and an apical spot on the elytra. 



Xylotrechus colonus. 



Black or dark brown; pronotum with light pubes- 

 cence on front and back margins; each elytron with a 

 narrow stripe of yellow pubescence running from the 

 scutellum to about the middle and then curving to the 

 outer margin, a short line of yellow in front of this and 



two behind it. Breeds in spruce and hemlock 



Xylotrechus undulatus. 



13. Pronotum with short, transverse lines or ridges.. . 14. 

 Pronotum without transverse ridges 17. 



14. Middle and hind femora spined at apex 15. 



Middle and hind femora not spined at apex; black; 



whitish pubescence on thorax; pronotum with narrow, 

 light, front margin; each elytron with a white or yellow 

 marking which nearly forms a circle near the base, a jagged 

 one just behind the middle, and an oblique one near the 



apex. Breeds in ash, elm, and hickory 



Neoclytus capraa. 



15. Pronotum with a longitudinal, elevated ridge; 

 antennae thread-like 16. 



Pronotum with a few distinct, transverse ridges 

 arranged in a median row; antennae thickened towards 

 the apex; reddish-brown; elytra dark behind the first 

 band and with four, nearly straight, narrow crossbars 

 of bright yellow pubescence, the one at the base the least 

 distinct. Breeds in a variety of trees such as elm, maple, 



black locust, hickory, and dog- wood 



Neoclytus erythrocephalus. 



1 6. Blackish; two vertical yellow bands on the front 

 of the head and three transverse ones on the pronotum; 

 elytra with the base reddish-brown, the scutellum and 

 three narrow curved bands yellow. Said to breed in 

 hickory, elm, and grape Neoclytus scutellaris. 



Very similar but the median yellow band is lacking 

 from the pronotum and there is often a red spot (not of 



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