54 WILLIAM G. DIETZ, M. D. 



EXPLANATION OF PLATE. 



1. Antenua of M. solutns. 



2. Lateral view of head of M. cryptops. 



3. Head and antennae of M. hyperodes ; 36, Head of same seen laterally. 



4. M. nevadensis. 



5. M. Ulkel. 



6. Front view of head of M. dorsalis ; 66, same seen from the side. 



7. Side view of head of 3/. interstifialis. 



8. 3f. Hornii % . 



9. " 9 . 



10. M. setiger % . 



11. Lateral view of head of M. deliaiibis : lib, posterior tibia of % of the same. 



12. Lateral view of head of M. sparsus. 



13. 31. rotundicollis. 



14. M. imbellis. 



15. 31. hirtellus : 1.56, head of the same seen from the side. 



16. 31. viUaticoUis. 



