INSECTS AND OTHER ANIMAL Pests [NJURIOUS TO FreLD BEAns 1019 
the strands of silk. Each brown area seen on a leaf represents the place 
of feeding of a mite below, and as these marks increase, the leaf becomes 
spotted, turns a sickly yellow, and in some cases drops. The lower leaves 
are attacked first, and as these are destroyed, the small creatures climb 
higher in search of new food. 
WHITE GRUBS, OR MAY BEETLES 
(Phyllophaga sp.) 
White grubs, the larvae of May beetles (Coleoptera, Scarabaeidae), 
tho occasionally found, have not been reported as a serious pest of field 
beans in western New York during the past four years. In 1917 the 
beetles were present in very large numbers around electric lights at Perry. 
The writer had 184 specimens, collected between June 12 and June 25, 
identified by Mr. Henry Dietrich, who found 137 Phyllophaga fusca 
Froh. males and 388 fusca females, and 6 P. anxia (dubia) Leconte males 
and 3 anaia females. P. fusca is believed by Forbes (1916) to pass thru 
a threz-years cycle. In 1920 a few beetles were collected around lights, 
but this brood was much smaller than the one observed in 1917. In rare 
cases the writer has found, in digging around a wilted bean plant, that a 
white grub had cut it off. Several plants of this type were found in 1919, 
and one beetle (fusca), bred from a grub found on July 3, changed to the 
adult stage on September 1. It*would have emerged normally in the 
spring of 1920. 
Injury from white grubs occurs usually when cultivated crops are 
planted after sod in a year following one in which there was a large emer- 
gence of parent beetles. The May beetles, according to Davis (1918), 
prefer to oviposit in fields of oats, barley, wheat, timothy, or sod, rather 
than in those where there are good catches of clover and alfalfa or where 
there are cultivated crops such as corn and beans. In western New York 
a common rotation is one of wheat, clover, and beans. If, in this New 
York rotation, the beetles are abundant during the year when a field is 
in wheat, there may be many small larvae present the next year; but, 
since the grubs do not seriously damage clover, the crop then growing, 
they might easily escape notice. As neither clover nor beans are at- 
tractive to the beetle for oviposition, it is evident that when this rotation 
is followed, little damage from the grubs should be experienced in western 
New York. Serious infestations of the grub occur only when pasture 
land or a crop of one of the small grains, such as barley, oats, or wheat, is 
followed the next year by beans. 
THE ROSE CHAFER 
(Macrodactylus subspinosus Fab.) 
In the summer of 1917, beans in many parts of New York were damaged 
by the rose chafer, Macrodactylus subspinosus (Coleoptera, Scarabaeidae). 
