44 Annals Entomological Society of America [Vol. X, 



3. The egg has certain definite and invariable external 

 characters which facilitate identification, viz., the dissimilarity 

 of the two ends, and the large, longitudinal fossa divided by the 

 longitudinal carina. 



4. Certain constant features with respect to the orientation 

 and oviposition were noted: (a) In the ovariole, the blunt, con- 

 cave end of the developing egg is nearest the terminal filament. 

 (b) On the petiole, the blunt end is directed towards the root- 

 stalk, (c) The long axis is parallel to the long axis of the petiole, 

 (d) The side of the egg opposite the fossa and carina is in con- 

 tact with the petiole, (e) The anterior end of the larva is devel- 

 oped in the blunt, concave end of the egg. (f) The ventral part 

 of the larva appears to invariably develop on the side opposite 

 the carina. 



5. Incomplete evidence indicates that the occurrence of 

 more than 7-9 eggs on a single petiole is due to oviposition by 

 two or more females. 



6. The position of the egg invariably marks the future 

 position of the so-called "gall." 



7. Microscopic examination of infested portions of the 

 petioles shows that a true gall is not formed, the result being 

 due to mere interior excavation. 



8. In addition to the possible production of nectar by 

 N. americana and its use as food, the adults were observed feed- 

 ing: (a) on the exposed tips of stamens, possibly consuming the 

 pollen; (b) on the exudation of broken, emergent flower stalks; 

 and (c) on the dead bodies of certain insects [Chironomus sp.). 



9. Field observations and experiments indicate that the 

 adults exhibit a distinct, positive reaction to sunlight. It 

 appears, however, that this positive phototaxis is overcome by 

 the stimuli inducing oviposition and by the stimuli inducing the 

 search for food. 



10. Adults of //. confluens were collected about the yellow 

 water-lily beds at Cedar Point, near Sandusky, Ohio, and 

 evidence pointed to them as active agents in the cross pollination 

 of these plants in that locality. 



