400 HOMES WITHOUT HANDS. 



which was a rootless plant of Stratiotes, on the afternoon of No- 

 vember 14. By the morning it had constructed a very perfect 

 oval cell, filled with air, about the size of an acorn. In this it 

 has remained stationary up to the present time. 



" No. 2. Nov. 15. In another vessel, also furnished with Stra- 

 tiotes, I placed six Argyronetras. The one now referred to began 

 to weave its beautiful web about five o'clock in the afternoon. 

 After much preliminary preparation, it ascended to the surface, 

 and obtained a bubble of air, with which it immediately and quick- 

 ly descended, and the bubble was disengaged from the body, and 

 left in connection with the web. As the nest was, on one side, in 

 contact with the glass, inclosed in an angle formed by two leaves 

 of the Stratiotes, I could easily observe all its movements. Pres- 

 ently it ascended again and brought down another bubble, which 

 was similarly deposited. 



" In this way no less than fourteen journeys were performed, 

 sometimes two or three very quickly one after another ; at other 

 times with a considerable interval between them, during which 

 time the little animal was employed in extending and giving 

 shape to the beautiful transparent bell, getting into it, pushing it 

 out at one place and amending it at another, and strengthening its 

 attachments to the supports. At length it seemed to be satisfied 

 with its dimensions, when it crept into it and settled itself to rest 

 with the head downward. The cell was now the size and nearly 

 the form of half an acorn cut transversely, the smaller and round- 

 ed part being uppermost. 



" No. 3. The only difference between the movements of this 

 and the former was, that it was rather quicker in forming its cell. 

 In neither vessel was there a single bubble of oxygen evolved by 

 the plant. 



"The manner in which the animal possesses itself of the bub- 

 ble of air is very curious, and, as far as I know, has never been 

 exactly described. It ascends to the surface slowly, assisted by 

 a thread attached to the leaf or other support below and to the 

 surface of the water. As soon as it comes near the surface, it 

 turns with the extremity of the abdomen upward, and exposes a 

 portion of the body to the air for an instant, then with a jerk it 

 snatches, as it were, a bubble of air, which is not only attached to 

 the hairs which cover the abdomen, but is held on by the two 

 hinder legs, which are crossed at an acute angle near their ex- 

 tremity, this crossing of the legs taking place at the instant the 



