CebrionidcB. — Aranea Domeslica. 283 



CEBRIONID^. STIRPS III. 



We are indebted to the kindness of another Entomological 

 Friend, for reminding us that Dr. Leach's third Stirps or Family 

 of Cebrionida?, are the females of the other Stirpes ; and that the 

 Cebrio brevicornis of Olivier, forming the genus Ilammonia, has 

 been for some years past, ascertained to be the female of Cebrio 

 gigas : see article Cebrio, in Did. Classique d'Hist. Nat. 



ARANEA DOMESTICA. 



Some years ago, when making some observations on the habits 

 of Spiders, I was struck with the following circumstance, which I 

 have never found in any author on the subject. I Insulated a com- 

 mon House Spider, by placing it on a little platform, supported by 

 a stick with a weight at the bottom, in the middle of a rummer of 

 water. The platform was abont \ an inch above the surface, 

 which was nearly even with the top of the glass. It presently 

 made its escape, as was anticipated, by suffering a thread to be 

 wafted to the edge of the glass ; but supposing that it might have 

 been assisted by the water being so nearly on the same level, I 

 poured some of it away, and placed the Spider as before. It de- 

 scended by the stick till it reached the water, and examined Avith 

 its two anterior feet all round, but finding no way to escape, it 

 returned to the platform, and for some time prepared itself by form- 

 ing a web, with which it loosely enveloped the abdomen, by means 

 of the hinder legs. It then descended, without the least hesitation, 

 into the water, to the bottom; when I observed the whole of the 

 abdomen covered with a web containing a bubble of air, which I 

 presume was intended for respiration, as it evidently included the 

 spiracles. The Spider enveloped in this little diving bell, endea- 

 voured on every side to make its escape, but in vain, on account of 

 the sllpperiness of the glass ; and after remaining at the bottom of 

 the water for thirteen minutes, it returned apparently much ex- 

 hausted, for it immediately coiled itself dooely under the little 



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