and Systematic Arrangement of British Spiders. 97 



contained in an exceedingly delicate tissue of white silk of a sub- 

 globose form, measuring ^th of an inch in diameter, which is 

 attached to the surface of the cell. The female, after the depo- 

 sition of her eggs, does not appear to quit the cell even for the 

 purpose of procuring food. 



A collection of spiders made by the Rev. Hamlet Clark in the 

 autumn of 1842, at Wappenham, in Northamptonshire, and 

 obligingly placed by him at my disposal, comprised specimens of 

 this species. 



Genus Argyroneta, Latr. 



66. Argyroneta aquatica. 



Argyroneta aquatica, Latr. Gen. Crust, et Insect, torn. i. p. 94 ; 

 Walck. Hist. Nat. des Insect. Apt. t. ii. p. 378. pi. 22. fig. 4 ; 

 Sund. Vet. Acad. Handl. 1831, p. 131 ; Hahn, Die Arachn. B. ii. 

 p. 33. tab. 49. fig. 118 ; Koch, Uebers. des Arachn. Syst. erstes 

 Heft, p. 14 ; Die Arachn. B. viii. p. 60. tab. 269. fig. 636 ; Blackw. 

 Linn. Trans, vol. xix. p. 116. 



Argyroneta aquatica habitually passes the greater part of its 

 life in the water, not only pursuing its prey in that liquid, but 

 constructing beneath its surface a dome-shaped cell in which it 

 places the cocoon containing its eggs ; this cell is supported in a 

 vertical position, the open part being directed downwards, by lines 

 of silk connecting it with aquatic plants, and, as it comprises a 

 considerable quantity of atmospheric air, the spider can at all 

 times occupy it without experiencing the least inconvenience. 

 In swimming and diving, the body of Argyroneta aquatica is more 

 or less enveloped in air confined by the circumambient water 

 among the hairs with which it is clothed, the supply being always 

 more abundant on the under than on the upper part in conse- 

 quence of the greater length and density of the hairs distributed 

 over its surface. 



This species is found in pools and ditches in various parts of 

 England. It is of frequent occurrence in the fens of Cambridge- 

 shire, from which locality I transported a pair to Crumpsall Hall, 

 near Manchester, in the summer of 1833; each was inclosed in 

 a small tin box, and did not appear to suffer materially from the 

 confinement. After the lapse of ten days, during which period 

 they were without water, I conveyed them to Oakland, in Den- 

 bighshire, where they arrived in perfect health. On placing one 

 of them in a large goblet more than half filled with water, it 

 speedily formed a dome-shaped cell beneath the surface, attach- 

 ing it to the side of the glass by means of numerous silken lines ; 

 being well supplied with insects, it lived in this state of captivity 

 till the commencement of winter, and on the temperature of the 

 room in which it was kept becoming much reduced, it entered 



Ann. §■ Mag. N. Hist. Ser. 2. Vol. viii. 7 



