121 



of insects is undoubtedly the neuration of the anterior wings, 

 and it may possibly be still further improved by carrying out 

 WesmaePs divisions, formed upon the differences of the neura- 

 tion of both the anterior and posterior wings. 



Synopsis of the Species. 



A. Div. 1. Abdomen petiolated. Ocelli in an equilateral tri- 

 angle. Antennae and tarsi simple. 



1. Crabro clavipes. 2. C. tibialis. 



B. Div. 2. Abdomen subpetiolated. Ocelli in an equilateral tri- 

 angle. Antennae and tarsi simple. Base of the meta- 

 thorax smooth and shining. 



3. Crabro dimidiatus. 4. C. signatus. 



C. Div. ,'1 Abdomen subsessile. Ocelli in an equilateral tri- 

 angle. 



* Antennae and tarsi simple. Base of the metathorax striated. 



5. Crabro luteipalpis. 6. C.proximus. / C. varius. 8. C. 

 transversalis. 9. C. vestitus. 



** Antennas and tarsi simple. Base of the metatkorax smooth 

 and shining. 



10. Crabro leucostoma. 11. C. anxius. 12. C. podagricus. 

 13. C. Walkeri. 14. C. Wesmaeli. 15. C. capitosus. 16. C. 

 bimaculatus. 17- C.pubescens. 18. C.obliquus. 19. C. pal- 

 lidipalpis. 20. C. vagabundus. 21. C. quadrimaculatus. 



*** Antennae simple. Anterior tibia of the males dilated. 

 22. Crabro scutatus. 23. C. cetratus. 



**** Antennae of the male with joints emarginate beneath ; their 

 tarsi simple. 



24. Crabro sexcinctus. 25. C. cephalotes. 26. C. interstinctus. 



Div. 4. Abdomen subsessile. Ocelli in an isosceles triangle. 



* Antennae of the males subfusiform. A 

 males scutellate. 



27- Crabro cribrarius. 28. C. patellatus. 



* Antennae of the males subfusiform. Anterior tibia of the 

 males scutellate. 



