BEHAVIOR OF SPIDERS AND OTHER INSECTS 401 



neled beneath the tile and thus reentered into the presence of 

 her ball. There she rested, calmly waving and cleaning her 

 antennae. He repeated the experiment with two individuals 

 of another species of burrowing beetles (5. atteles) ; but each 

 scampered off as soon as she was placed on the outside of the 

 enclosure. This is an interesting display of maternal instinct. 

 Benard thinks that the beetle reflected. Undoubtedly we have 

 hesitation followed by action; but, may we not interpret it 

 in the following manner ? A stimulus from her ball, plus 

 certain internal factors, was impelling the beetle to draw 

 near to the ball; the grasp of the hand produced a stim- 

 ulus, which, coupled with certain internal conditions, tended to 

 induce the insect to flee. As the beetle moved farther and 

 farther from the enclosure the effect produced by the grasp of 

 the hand became gradually weaker and weaker until it was 

 too feeble to affect conduct. The effect of the stimulus from 

 the ball still persisting forced the creature to return to the en- 

 closure. Burrowing is one of the normal instinctive activities 

 of the burrowing beetle, hence, when unable to scale the wall, 

 it naturally would resort to digging. 



Four years ago, Roubaud,* in a single genus (Synagris) of 

 potter wasps, discovered one species which stocked its burrows 

 with enough caterpillars to last its larvae until they were ready 

 to form pupae; another which placed a few caterpillars in each 

 burrow and then brought more as the young needed them, and 

 yet a third species which stored no food in its nest, but collected 

 it and fed it to its hungry babes. Recently Wheeler (120) has 

 discovered a mining wasp (Aphilanthus frigidus) which, in its 

 maternal behavior, is intermediate between a form like Bernbex, 

 which captures as needed the food with which to feed her hungry 

 larvae and those forms which stock their burrows with provis- 

 ions, lay their eggs, and then pay no further attention to them. 

 He found these wasps at Blue Hills, near Boston. Each colony 

 covered several square yards and contained from 30 to 60 nests. 

 The burrow, which is about one-fourth of an inch in diameter, 

 descends obliquely and abruptly for from six to eight inches 

 and terminates in a pocket. Similar pockets are attached to 

 the side of the common hallway. When the ants of the genus 

 Formica are having their nuptial flight, these wasps capture 



* Ann. R. Smith. Inst, for 1910, pp. 507-526. 



