GRAPE-BERRY MOTH TN NORTHERN OHIO. 33 
MATING. 
Mating was observed but once, this in the insect ary on July 19, 
1917, at 2.45 p. m. The moths emerged the day previous and the 
jar contained 4 males and 10 females with a sprig from a grapevine 
bearing a grape leaf and cluster. The moths were on the bottom of 
the jar, not mounted, but with their bodies in opposite directions, the 
posterior parts touching. 
OVIPOSITION. 
The following observations on oviposition were made in a heavily 
infested part of a large vineyard on June 30, 1917. Oviposition 
began about sundown or 6.30 p. m. When the moths first appeared 
they fluttered nervously about the vines, alighting seemingly at 
random, generally upon clusters, though often upon stems or leaves. 
Upon finding a cluster a moth would walk rapidly about upon a 
grape berry, covering practically the entire surface. Finally becom- 
ing quiet she would flex the abdomen until its tip touched the berry. 
During the process the abdomen twitched or shook slightly but the 
tip was at no time lifted and then replaced. The deposition of the 
egg required less than a minute's time but was not instantaneous. 
Upon completion of the deposition of a single egg the moth usually 
flew nervously away from the cluster. The following exception 
occurred among four depositions observed. A moth alighted upon a 
grape and oviposited immediately without any preliminary inspec- 
tion and upon completion walked directly onto the next grape in the 
same cluster and repeated the operation. 
The spring brood of moths deposits a considerable percentage of 
the eggs near the attachment of the grape to the cluster, and the 
first-brood moths seem frequently to select a place on the underside 
of the cluster, away from the light. 
Repeated observation has shown that the moths discriminate 
between sprayed and unsprayed grapes as places for oviposition. 
This was most marked in one experimental vineyard in 1916. Four 
rows had been left unsprayed and the adjoining rows sprayed, with 
the exception of the side of one row next to the checks. This row was 
thoroughly sprayed from one side by the trailer method and the grape 
clusters well covered on that side. About a third of the surface of the 
clusters remained unsprayed and deposition by first-brood moths 
was apparently as heavy on this unsprayed surface as on the adjoin- 
ing check rows, whereas practically no eggs were deposited on the 
sprayed side of the same clusters. This observation led to continued 
study on the same point and it was substantiated repeatedly during 
the investigations. That eggs are deposited to some extent on the 
sprayed surface has been shown by infestation of sprayed plats. 
That early blooming varieties of grapes are more heavily infested 
than mid-season varieties has been known generally among grape 
