Bramble-Dwellers 



It was easy to repeat the experiment with- 

 out changing anything in the natural condi- 

 tions, except the direction of the cocoons : all 

 that I had to do was to hang up some bram- 

 ble-stumps as I found them, vertically, but 

 with the opening downwards. Out of two 

 stalks thus arranged and peopled with Osmiae, 

 not one of the insects succeeded in emerging. 

 All the Bees died in the shaft, some turned 

 upwards, others downwards. On the other 

 hand, three stems occupied by Anthidia dis- 

 charged their population safe and sound. 

 The outgoing was effected at the bottom, 

 from first to last, without the least impedi- 

 ment. Must we take it that the two sorts of 

 Bees are not equally sensitive to the influences 

 of gravity? Can the Anthidium, built to pass 

 through the difficult obstacle of her cotton 

 wallets, be better-adapted than the Osmia to 

 make her way through the wreckage that 

 keeps falling under the worker's feet; or, 

 rather, may not this very cotton-waste put a 

 stop to those cataracts of rubbish which must 

 naturally drive the insect back? This is all 

 quite possible; but I can say nothing for cert- 

 ain. 



Let us now experiment with vertical tubes 



38 



