365 



Diving Water-Spider. 



That spiders may be able to breathe under water, 

 we can well understand from their breathing hke 

 amphibious reptiles by means of gills; but there is an 

 aquatic spider {Argijroneta aquatica, Walckenaer) 

 which is not contented, as a frog would be, with the air 

 furnished by the water, but actually carries down a 

 supply of air from the atmosphere to her subaqueous 

 nest. This spider does not like stagnant water, but 

 prefers slow-running streams and ditches where she 

 may often be seen, in the vicinity of London and else- 

 where, living in her diving-bell, which shines through 

 the water like a little globe of silver: her singular 

 economy was first, we believe, described by Clerck,* 

 L. M. de Lignac,! and De Geer. 



" The shining appearance," says Clerck, " pro- 

 ceeds either from an inflated globule surrounding the 

 abdomen, or from the space between the body and the 

 water. The spider when wishing to inhale the air, 

 rises to the surface with its body still submersed, and 

 only the part containing the spinneret rising just to 

 the surface, when it briskly opens and moves its four 

 teats. A deep cone of hair keeps the water from 

 approaching or wetting the abdomen. It comes up 

 for air about four times an hour or oftener, though 

 I have good reason to suppose it can continue with- 

 out it for several days together. 



" I found in the middle of May one male and ten 

 females, which I put into a glass filled with water, 

 where they lived together very quietly for eight days. 

 I put some duck weed (Lemna) into the glass to 

 aftbrd them shelter, and the females began to stretch 

 diagonal threads in a confused manner from it to the 



* Aranei Suecici, Stockholm, 1757. 

 t Mem. des Araign. Aquat. 12mo. Paris, 1799. 

 vor,. IV. 31* 



