ScHAW. — On Sijiders. 107 



Art. V. — Notes on Spiders. 

 By Major-General Schaw, C.B., E.E. 



[Read before the Wellington Philosophical Society, 11th October., 1893.'] 



1. How do the ordinary spiders which make geometric webs 

 convey their lines across streams of water? 2. Do they see 

 the opposite shore, or what is their extent of vision? 



To obtain answers to the above questions, a potato, with a 

 slice cut off it to give it a level base, was placed on the bottom 

 of a large dish of water. Two sticks were stuck into the 

 potato, about Sin. long, and 2in. apart at bottom, 4in. 

 at top. 



First a large spider was placed on one of the sticks. He 

 ran up and down the stick, and then remained quiet. 



Then a very small spider was placed on the same stick. 

 It ran straight at the large spider, which instantly grappled 

 with it. The small spider escaped by dropping into the water 

 (without any line attached, for which apparently it had no 

 time). It was carried down to the potato by the force of its 

 fall, and for more than a minute it travelled round and round 

 the potato, under water ; then it rose to the surface and lay 

 still until blown to the stick, up which it ran nimbly, without 

 having suffered apparently from its adventures under water or 

 on its surface. 



A medium-sized spider was then placed on the top of the 

 stick. It dropped by a spun-out line to the surface of the 

 water, felt it with its feet, and having thus ascertained, ap- 

 parently, that it was imprisoned it climbed up its line again 

 (the line seemed to be coiled up or carried up with it as it 

 ascended). It then began to draw out line from the spin- 

 nerets with its legs, and to throw it out to leeward (there was 

 a slight draught from the open window). The operation was 

 very suggestive of throwing out a fishing-line. When about a 

 foot of line had been thus thrown out floating in the air the 

 creature ceased, and seemed to wait for it to catch on som 

 thing. As there was nothing on which it could catch within 

 8ft. or 10ft. of it in the direction in which it was carried 

 by the draught of air, I brought a vase of flowers on the 

 table near enough to let the line touch some leaves, to 

 which it seemed to adhere. Immediately the spider began to 

 pull on the line, evidently to test if it was firmly attached, and 

 it was just starting to climb out on to its bridge when unfor- 

 tunately the large spider came blundering on to the scene, and 

 ran up against the worker. There was a short conflict, and 



