New York Agricultural Experiment Station. 473 



egg usually comes to lie nearly parallel to the surface. It generally 

 takes from six to ten minutes to force the ovipositor to its base the 

 first time, but in some cases it takes much longer, depending on the 

 resistance of the bark. After the operation this organ is pulled 

 nearly out and drilled in again several times, each effort taking about 

 one and a half or two minutes. When the hole is sufficiently reamed 

 out and the ovipositor drilled in for the last time the female forces 

 out a drop of excrement and, by stretching out the tip of the abdomen, 

 fastens it to the bark just below the hole. The egg is then forced 

 down and the ovipositor is slowly withdrawn. The female pauses 

 with only the tip remaining in the hole and deposits some mucilaginous 

 substance. She then removes the ovipositor, moves a slight distance 

 backward, seizes the drop of excrement in her mouth and places it 

 over the opening. She then spends several minutes packing it in 

 and smoothing it out so that the wound is neatly capped. (Fig. 31, c.) 

 The whole process of depositing an egg, from starting to drill until 

 the hole for the reception of the egg is sealed, may consume from 

 twenty minutes to three-quarters of an hour. In our breeding cage 

 experiments from one to thirteen eggs were deposited in a single night 

 by one individual. Several of the insects laid a few eggs every night 

 during the whole period of oviposition. On a few nights others 

 did not oviposit at all. The largest number of eggs deposited by 

 a single female was seventy-five, the smallest number twenty-four, 

 and the average of eleven individuals was forty-nine. 



The eggs are laid in the soft inner bark. A groove is often cut 

 in the surface of the wood, but generally the hard ti.ssues are not drilled 

 into to any extent. In most plants a hard, woody capsule forms 

 around the egg which completely encloses it with the exception of that 

 portion in contact with the opening made by the ovipositor in the bark. 



In trees having a rather soft, fleshy bark, such as apple and plum, 

 niveus prefers to oviposit in fairly large branches from one to three 

 inches in diameter. The eggs may be placed in almost any area 

 in the bark, but a favorite location is in a lenticel where the initial 

 drilling is more easily accomplished. (Plate XXXI, fig. 1.) In bushes 

 and trees in which the large branches have a tough bark the eggs 

 are commonly laid in the smaller branches in thick places in the bark 

 on each side of the base of a small twig or bud. In raspberry canes, 

 where the eggs are sometimes fairly common, oviposition usually 

 occurs in the fleshy area at the side of the bud in the axils of the 



