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of earth thrown up for rock-garden purposes. The entrance is 

 on the south side, and only a few inches from the high wall of 

 twine-netting that bounds the tennis court at that end. This 

 netting is of inch-and-a-quarter mesh ; and whilst the wasp colony 

 was small it did not appear to interfere greatly with their coming 

 and going. The wasps on leaving the nest divided into three 

 parties — two turning sharply to right and left respectively and 

 flying N.E. and N.W. to the upper branches of a row of poplars. 

 Among their captures from the poplars I could frequently detect, 

 small green larvje about an inch long. The third party went 

 forward through the netting, and over the tennis court. Now, in 

 returning to the nest these had no difficulty, they flew straight 

 through at full speed ; but in leaving the nest most of them 

 boggled at it, and dodged about before deciding which of the spaces 

 to pass through. By the middle of August, when the number of 

 the workers had enormously increased, the net had become an 

 obstacle, and the cause of much confusion between the coming and 

 going streams. On August 18th I observed that three or four 

 workers were hanging to the threads of the net as though resting. 

 Closer observation showed that they not only clung with their 

 feet, but that the thread was gripped by the mandibles, and that 

 the wasps were revolving on this axis. Then it struck me that 

 they might be cutting the net, and I found that several of the 

 meshes had already gone. I watched the work at intervals during 

 that and the next two days, and several times saw a worker give 

 up and retire into the nest, her place being taken a minute or so 

 later by another worker from the nest. Of course, it may have 

 been the saiiie one returned, but I fancy they were working on 

 the spell system. On the third day the task was complete, a 

 hole a foot in diameter having been made, through which the 

 outgoing workers could shoot swiftly, straight from the entrance 

 hole. 



" The gap was neither round nor square, nor any other definite 

 shape, the result being achieved piece-meal. A good deal of 

 unnecessary labour had been expended, owing to their efforts not 

 being restricted to the circumference of the projected hole. 

 Wishing to make sure that the work had been deliberately under- 

 taken with a definite purpose, I covered the opening with a 

 sound piece of net, on August 24th. I waited until 7.30, when 

 the outward stream had ceased for the night, and the inward 

 stream had dwindled considerably. At 8.30 a.m., on the 25th, there 

 was a new hole about half the dimensions of the old, and only 



