154 Annals Entomological Society of America [Vol. XII, 



EXPLANATION OF PLATES VII, VIII AND IX. 



Wing of Erax: 



. 1, stramineus; 2, barbatus; Z, jubatus; -1, aestuans; 5, anonialus; 6, califoniicus. 



Hypopygium of Erax, dorsal view: 



13, prattii; 14, coquillettii; 15, pilosiis; 16, tabescens; 59, varipes. 



Hypopygium of Erax, lateral view; 



7, willistoni; 8, barbatus; 9. bicolor; 10, anomnlus; 11, candidus; 12, pernicis; 

 17, asluans; 18, apicalis; 19, kansensis; 20, loewii; 21, belfragei; 22, az<n- 

 mystaceus; 23, fulvibarbis; 24, portoricensis; 25, slossonce; 26, tabescens; 

 27, mexicanus; 28, affinis; 29, nigritarsis; 30, ntfitibia; 31, nigrimystaceus; 

 32, stylatiis; .33, stramineus; 34, cingulatus; 35, argentifrons; .36, haloesus; 

 37, interriiptus; 38, canus; 39, splendetts; 40, argyrosoma; 41, rapax; 42. a?<ri- 

 vestitus; 43, texaniis; 44, pallidulus; 45, truncatus; 46, eximeiis; 47, auripilus; 

 48, plenus; 49, varipes; 50, cressoni; o\, nemoralis; 52, subcupreus; 53, costalis; 

 54, jiibatus; 55, parvulns; 56, latrunciihis; 57, concinnatus; 58, carinatus; 

 60, unicolor. 



