HAPDWICKE'S SCIENCE-GOSSIP. 



109 



necting medium is apparently a long membranous 

 neck, which ultimately diminishes into a single 

 cord, thus becoming gradually more attenuated 

 until it finally separates, and the two are perfected. 

 The complete division from the first iudenture to 

 the final severance occupied about thirty-five 

 minutes. All the A. Sol have what is termed a 

 contractile vesicle (fig. 65, e). This is never still, 

 day or night, but is continually but slowly swelling 

 up. When at a certain height it suddenly collapses 

 and disappears, but only for a short time, when it 

 again swells and again collapses, occupying from 

 ten to thirty seconds in its development. 



Fig. 69. Spines crossing in the process of self-division. 



The mode of nourishment in these minute crea- 

 tures is a subject of the highest interest, for they 

 live on solid nutriment, and reject such parts as are 

 indigestible. They feed on infusoria of all kinds, 

 and the lower alga?, such as the diatomaceaj, and on 

 crustacean. 



I have had the A. Sol under observation for more 

 than two months, and have seen and noted some 

 very interesting things concerning them, which, if 

 acceptable to the readers of Science-Gossip, will 

 form the subject of another communication. 



"The diffusion of Christian knowledge insures 

 the progressive advancement of mau in those high 

 moral and intellectual qualities that constitute his 

 true dignity." — Mrs. Somerville's " Physical Geo- 

 graphy" 



MODE OF SEARCH AND CAPTURE OF 

 SPIDERS. 



By the Rev. 0. P. Cambridge. 



"17S7~1TH regard to the search for spiders and 

 their capture, it might almost be sufficient 

 to say search everywhere, and capture in every pos- 

 sible or practicable way ; but still it may be useful, 

 as the result of experienca, to make a few more 

 detailed remarks upon those heads. There is 

 scarcely any conceivable locality but what some 

 species or other of spiders may be found in it, and 

 therefore none should be set down a priori as un- 

 likely, or not worth a close examination ; among 

 many other favourable localities, however, may be 

 mentioned, particularly, loose bark of trees, under 

 which numerous species conceal themselves by 

 day, and many others dwell entirely, forming under- 

 neath it their snares and egg cocoons ; beneath 

 stones and detached pieces of rock myriads of 

 spiders dwell; in this habitat are found many of 

 the Drassides, a numerous, and, though generally 

 plainly coloured, exceedingly interesting group ; 

 among rubbish and heaps of debris, wood, brickbats, 

 or what not; beneath and among cut grass, and 

 rushes or reeds which have lain some little time 

 after cutting ; also among grass or other herbage, 

 near its roots, numerous species seldom to be seen, 

 and rarely procured elsewhere, live and secrete 

 themselves ; also among mosses, lichens, and dead 

 leaves, may be found many minute spiders, not to 

 be obtained except by a careful search among such 

 materials. Water-weeds and debris, collected in 

 marshes or on the borders of ponds and streams, 

 are also most favourable for the hiding-places and 

 habitations of many peculiar species seldom found 

 in other localities. I have not mentioned such 

 obvious habitats as trees, bushes, blossoms of 

 flowers, the general surface of the earth, rocks, 

 and stones in every locality, houses, and old build- 

 ings of all kinds, outer walls of houses, palings, 

 tree-trunks, &c. &c. ; in all these, spiders force 

 themselves upon the collector's attention, but in 

 the others before-mentioned they must be searched 

 for carefully, and often painfully. Some spiders 

 again (though of small size) are quasi-parasitic, 

 living on the outskirts of the webs of larger species. 

 Those at present known consist of a single genus, 

 or perhaps two genera, of which several species 

 have been described, and others are known. They 

 are of the genera before-mentioned — Argyrodes and 

 Arianne. These inhabit the webs of large Epeirids, 

 and appear to live on the smaller insects caught in 

 them ; probably also spinning their own irregular 

 snares among the larger lines of the geometric web. 

 The webs, therefore, of large Epeirids, especially 

 of those which live in colonies like the Epe'ira 

 opuntice of Europe and Asia, should be searched 



