326 The Ohio Naturalist. [Vol. XIV, No. 7, 



b}^ the dark cavity beneath. The plug often so closely resembles 

 the surrounding surface as to be very difficultly distinguished, and 

 some practice is required to locate these eggs. If more than one 

 discharge is present, however, the plug is easily seen. 



DESCRIPTION OF THE EGG. 



The egg is a small, glistening, opaque, somewhat "pear-shaped" 

 body of a creamy white color. The size varies somewhat, but the 

 average dimensions are about .643 mm. long by .289 mm. in dia- 

 meter at the largest ]5art. It consists of an outer, comparatively 

 tough membrane, filled with an opaque, sticky fluid. The large 

 end of the egg is placed toward the inner end of the cavity, while 

 the small end is attached to the plug in the mouth of the cavity, 

 which does not agree with the observations of Hinds and Turner 

 (3) who describe the egg as having the "larger end outward as it 

 rests in the grain." On the small end of the egg is a small pro- 

 tuberance that fits into the pit in the inner surface of the plug. 



DESCRIPTION OF THE CAVITY. 



The cavity is somewhat larger than the egg, there being an 

 unoccupied space around the sides and bottom. The bottom is 

 evenly rounded, the sides drawing gradually together at the mouth, 

 the diameter of \'\'hich is smaller than at any other part of the 

 cavity. The mouth of the cavity being smaller than the larger 

 end of the egg, it is necessary to enlarge the opening in order to 

 remove the egg. 



SIGNIFICANCE OF THE HABIT. 



It is interesting to conjecture the uses of this careful and 

 laborious method of oviposition. The point of ]:)rime importance 

 is that the eggs are placed in such a position that the larva; pro- 

 duced are surrounded by an abundance of food, and are in a posi- 

 tion where they are protected during the helpless period of life. 

 By being deposited beneath the surface of the corn, the eggs are 

 protected to a large extent from external injury, from excessive 

 drying, and from sudden changes in temperature. While serving 

 to increase the protection from external injur3^ excessive drying, 

 and change in tem])erature, the sealing of the cavity is undoubtedly 

 useful as a protection against predaccous and jjarasitic enemies. 

 Incidentally, this, probably, is quite effective as a ])rotection to the 

 eggs and larvag against gases iised in fumigation. 



As a protection against natural enemies, the i^lug is no doubt 

 serviceable, but it is not an absolute, and possil^ly not a very highly 

 efficient safeguard, for, while making these observations, the 

 writer noted numerous instances in which the predaccous mite, 

 Pediculoides vcntricosus Ncw]3ort (2), successfully attacked and 



