248 
Ohio Biological Survey 
EXPLANATION OF PLATE IX. 
Corythucha arcuata Say (after Morrill). 
Fig. 1. Laterval view of egg. 
Fig. 2. Apical end of egg showing cap. 
Fig. 3. Nymph, first instar. 
Fig. 4. Trumpet-shaped spine, arising from a subconical base. 
Fig. 5. Nymph, second instar. 
Fig. 6. Nymph, third instar. 
Fig. 7. Nymph, fourth instar. 
Fig. 8. Trumpet-shaped spine arising from a long thick protuberence. 
Fig. 9. Nymph, fifth instar. 
