54 ILLIXOIS BIOLOGICAL MONOGRAPHS (54 



EXPL^NATIOX OF PLATE I 



DORSAL ASPECT OF THE HEAD 



Fig. 1. Hjpothetical t)-pe. 



Fig. 2. Telracha Carolina. 



Fig. 3. Ckindela formosa. 



Fig. 4. Calosoma calidtim. 



Fig. 5. Harpalus erralkus. 



Fig. 6. Amphizoa leconki. 



Fig. 7. Omophron americatium. 



Fig. 8. Peltodyles IZ-punclaUts. 



Fig. 9. Cybister fimbrwlatus. 



Fig. 10. Dincuks amcricanus. 



Fig. 11. Hydracna marginkollis. 



Fig. 12. Hydroscapha nalans. 



Fig. li. Hydrous Irmngularis . 



Fig. 14. Hydro philus obtusatus. 



Fig. US. Platypsyllus castoris. 



Fig. 16. Brathimus nitidus. 



Fig. 17. Leplimis leslacetis. 



Fig. 18. Necrophorus caroliniis. 



Fig. 19. Clambus puberuius. 



Fig. 20. Connophron fossiger. 



Fig. 21. Molamba liinata. 



Fig. 22. Slenus flavicornis. 



Fig. 2.'. Harpalus erralkus, cross-section of cephalic end of the dorsal aspect of the head. 



Fig. 24. Harpalus erraticus, showing invagination of the front. 



aa antacoila fcs fronto-cljpeal suture 



aj antafossa ]e frontal ridge 



an antacoria / labrum 



ccn cer\'inotum oc occiput 



ce compound eye ol oculata 



cj clypofrons as occipital suture 



d clj-pealia pe precljpeus 



ea epicranial arm pn pretentorina 



eo exoculata po postclypeus 



es epicranial stem sn supratentorina 



f front I' vertex 



