THE CANADIAN ENTOMOLOGIST. 259 



many capped cells in the comb. In about a week I had a colony in full 

 career, and it soon became so populous that I was obliged to remove 

 many of the adults. This was accomplished with the aid of a long pair 

 of forceps manipulated through a trap door. 



As my primary object was to secure the coveted males of Xenos, I 

 was not a little chagrined and surprised to find that these continually 

 escaped me, and in some mysterious manner disappeared, so that I was 

 not even gratified with a glimpse of one of them. That they were pro- 

 duced within the vivarium I could not doubt. The empty capsules pro- 

 truding from the bodies of many of the wasps were evidences of this, 

 and the little mask-like lids which lay plentifully scattered about on the 

 bottom of the box confirmed the fact. Moreover, many wasps a day or 

 two old wandered about with the Uttle faces of the unopened male 

 capsules grinning at me from between the joints of their bodies, as if 

 mocking at my discomfiture. 



At last, early one morning, chancing to take a look at my captives, I 

 observed the whole society in a state of great excitement. Wasps stood 

 about with wings half raised or vibrating angrily, with antennae 

 alert and watchful, while now and again one of them would make a sud- 

 den dart with its jaws at an invisible object in the air. The whole com- 

 pany seemed bewitched. Steadying my eyes and watching closely I 

 began to see several misty little objects darting with fury about the box. 

 ever and anon dashing among the wasps, which, like cattle attacked by 

 gad-flies, huddled together in groups and awaited the onslaught. In the 

 dim half light of the early morning I could not follow their rapid move- 

 ments with my eyes, but their whereabouts could be told, from time to 

 time, by the commotion among the wasps whenever one of them ap- 

 proached very near. Finally, on the floor of the cage, a male Xenos sud- 

 denly made its appearance, spinning round and round on its back like a 

 fly with its wings burned in a candle flame. A Polistes standing near the 

 spot promptly pounced upon it, and, before it could be rescued, had re- 

 duced it to pulp in its jaws. In the same manner I lost, one by one, all 

 of the four or five specimens that were abroad at that time. Such was the 

 watchfulness of the wasps, and so great their hatred and fury against these 

 little persecutors, that in spite of all precautions nearly all the male para- 

 sites were captured and destroyed before I could lay my hands on them. 

 I succeeded in saving not more than half a dozen specimens out of more 

 than a hundred that were set free in the box. As no additions were made 



