` .· s , ;i:j,;
  · 7 -  
  On cm Injury io Fruiisiby Insects and Birds. 69      
l,   mental plot on the farmfithat each year. is enriched with stable ~    
11   manure, is always badly infested, and would be ruined if we did      
is   not have a man go through. the corn frequently when the beetles      
if   are about and knock them into a pan or bucket of water on the ` -    
e   surface of which is a little coal oil. Other plantings of corn on ` .  
a the farm are but little, and soinetiinesnot at all, injured by the l   *  
*, l insect. This little plot,} therefore, atfordsan excellent illustra—    
e   tion of a danger that mayylurk in a free use of stable manure on '_   "_1,`i  
e   i land to be planted in corn,—a danger not from the grubs living 1 ‘  
y   in the manure, butifromthe beetles which they produce.    
y   The life—history of the insect as we have learned it from _  
f l both indoor and outdoor observations is as follows: ·  
t i In egninement theibeetles placed eggs in the soil during the ·  
’ i last week of July in 1S96,·one individual having deposited its  
I { complement on July 23. They were an inch br two below the· y  
_   surface, generally at the sides of the flower pots used to confine .  
3   the beetles. Young grubs were found to have hatched from these il  
S . eggs on August 20, and were then from one-fourtli to one-half ·  
r inch longf They continue to feed and grow from‘this time for- I t  
)   I ward until cold weather sets in, being then about two—thirds '  
_ y grown, thick-bodied grubs, living a few inches benegth the sur- .  
; y face in burrows which they keep open as long as the weather .  
t remains mild, and would undoubtedly keep open all winter if the y  
I cold did not become severe. `ln 1895 in building the Vivarium  
belonging to this Division, land was enclosed by the walls of the  
glass-covered portion that had had manure scattered on it re- ,  
cently, and in consequence the grubs were very abundant i11 the  
y enclosed spacef Their presence was recognized first by the rather y  
‘ broad trails they made in traveling about on the surface, for it is  
_ thei1·`l1abit to leave the burrows at_ night for this purpose, when 5 
they travel with considerable address by turning over on their y  
backs and propelling the heavy body along by contractions of  
muscles within. They may be distinguished among grubs  
infesting the soil by this peculiar method of locomotion.  
The house was not heated, yet the grubs remained active all win-  
tor, quickly opening the entrances of their burrows when these  
Were closed by our operations, and coming out and wandering  
 
 
 
 
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