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rocks between the tide-marks on the shore, and, by spinning a 

 closely-woven web of silk over the entrance* imprison a mass of air 

 in which they are able to live during the flood-tide." The interesting 

 point here is not the carrying down of air to be used under water, 

 but the capturing and retaining of air already possessed. The 

 closely-woven web of silk, besides enclosing air for use, would, no 

 doubt, also act as a protection, preventing the Australian spider from 

 being washed out of its crevice by the waves. At the same time, the 

 situation is precisely that of A. aquatica living in air enclosed by a 

 closely-woven web of silk under water, and able to prevent the water 

 from penetrating into its haunt. 



Passing now to matters purely descriptive, and in a small measure 

 personal, as far as observation is concerned, it may be well to state, 

 by way of preface, that this spider, included by Mr. Blackwall in the 

 family Drassidae, seems to have definitely found its place among the 

 Agelenid^e. Among other structural reasons Mons. E. Simon (" Les 

 Arachnides de France " ) notices that A. aquatica has three, not two, 

 tarsal claws {gn'ffes Airsa/es), a fact which alone would exclude it 

 from the already somewhat crowded family Drassidae. In A. aquatica 

 the two upper claws are toothed, the lower plain. The striated or 

 indented cephalothorax, which Mons. Simon mentions among the 

 features of the Agelenidae, is also noticed in A. aquatica^ the sides of 

 the shield being strongly wrinkled. The legs and cephalothorax are 

 brown with a reddish tinge, the abdomen is dark olive. The female 

 averages half an inch in length, the male being still larger — an 

 unusual feature among spiders ; but Mons. Simon draws attention to 

 the fact that the males of Agelenidre are, on the average, equal in 

 size and strength to the femajes, and, though severe struggles some- 

 times take place on the web they are not, as in the case of Epeiridae, 

 overcome and eaten. The legs of this species are long and hairy, 

 well adapted for swimming. The order is somewhat remarkable : 

 male, i, 4, 2, 3 ; female, 4, i, 2, 3. When we remember that the 

 female, when making her nest, brings down a considerable globe of 

 air, which she holds with her hind legs, and releases into the dome 

 which she is making, the advantage of their length is obvious. 



I had frequent opportunities, many years ago, when living in 

 North London, of obtaining these spiders from ditches near the Lea, 

 at Tottenham. The following are the proceedings of a female, 

 before laying her eggs, which were hatched in due course in my tank. 

 A silken dome was spun among some leaves o{ A/iacharis alsinastrum. 

 This was the mere roof of the dwelling. The spider then rose, and, 

 elevating her abdomen out of the water, entangled a quantity of air, 

 which, joined to the bubble usually around her body, gave her an 

 extra supply. She then descended, holding this air with her hind 

 legs till she came under the dome, when she released it. The silk 

 which she had spun and the leaves and stalk of the plant held the 

 bubble ; and the spider kept bringing down fresh supplies of air till 

 a bubble about the size of a hazel-nut was formed. Round this she 



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