2 ‘BULLETIN 352, U. S. DEPARTMENT OF AGRICULTURE. 
life history, and the means for its control. The work herein dis- 
cussed was conducted at North East, Pa., during the season of 1915. 
FOOD PLANTS. 
In the region covered by the writers’ observations the natural food 
plant of this insect is the pin, fire, or bird cherry (Prunus pennsyl- 
vameca). (Pl. I; Pl. V, A and B.) Wild black cherry (P. serotina) 
and chokecherry (P. virgunana) are entirely immune from attack, 
even by the beetles. Among cultivated fruits only sour cherry and 
peach trees are attacked. Even in the sour cherries those varieties, 
such as the Early Richmond, which have comparatively thin foliage, 
are much more seriously injured than the thicker leafed varieties. 
Sweet cherry and plum, common report to the contrary notwith- 
standing, are not at all eaten. The beetles have frequently .been 
found on these trees, but never feeding. Color is lent to the belief 
that they attack plums by the very general prevalence of the shot- 
hole fungus on these trees, casual observers taking the holes caused 
by the fungus to be the feeding marks of 
the beetles. 
All of the foregoing observations in 
relation to cultivated trees apply to the 
adult beetle. On only one occasion were 
larve found on anything other than the 
pin cherry. On August 24 two larve 
were found on leaves of Early Richmond 
cherry. One of these had attained nearly 
full growth, while the other was still in 
| - the first stage. Neither of them lived to 
Peete ty ta eee (caieruedia maturity. In the confinement of cages 
larged; natural size at right. (Origi- larvee of the second and third stages fed 
ee sparingly on leaves of cultivated cherry, 
but first-stage larve died without feeding. One lot of 57 newly 
hatched larvee were fed on peach leaves, but within 6 days all were dead. 
From the records just given it appears that, except in the adult 
stage, this species is not likely ever to become of economic importance. 
The beetles are mentioned in literature as having been taken on 
various other plants, such as apple and chestnut, but these were 
probably merely strays, although Davis (1896)! states definitely that 
they attacked apple in Michigan. The apple was, however, entirely 
immune to attack during the present outbreak. 
Lugger (1899) mentioned ‘‘native plum” as a natural food pm as 
well as the ‘‘fire cherry.” 
The old idea that G. rufosanguinea Say is a Southern form of cavi- 
collis together with an obvious mixing of data has led to the inclusion, 
in literature, of Ranunculus acris, a buttercup, among the host plants 
of cavicollis. G. rufosanguinea is known to breed on wild azalea. 
1 Dates in parentheses refer to the Bibliography, p. 25. 
Se ES TE = 
cenit pata ie 
SL Ss 
