TRANSACTIONS OP THE SECTIONS. 163 



gusty weather this is strengthened by additional layers of silk, to which are added 

 lef^s, ^\'ino■s, &e., the refuse of their prey. Many spiders manifest proofe of great 

 atfection for their olfspring : the female Lycosce carry their cocoons constantly about 

 with them, attached to their spinners ; and when the young are hatched, they affix 

 themselves to the hairs on the legs, abdomen, &c. of their parent. Pholcus ^^halan- 

 gioides carries its cocoon in its mouth : Dolomedes mirahilis also, attaching a few 

 lines fi'oni the spinners as well ; it is only left to take food. The yoimg of many 

 species of Theridioti live with their parent for some time in a tent constructed by 

 her, and are, tiU able to shift for themselves, supplied by her with food. 



The structure of many spiders presents nimierous points of interest. In Atyjnis 

 Sulzeri, our only British yepresentative of the gi'eat Bird-catching Spiders of the 

 tropics, the jaws are so enormously developed as to render necessary an unusual 

 elevation of the fi-ont of the ceplialothorax, at the highest part of which, on a short 

 column, the eyes are seated. This spider constructs a long tube of silk in a burrow 

 foi-med in sloping banks, like its relative the "Trap-door spider;" the entrance, how- 

 ever, is protected in a different way — the end of the tube, hanging out in a collapsed 

 state, lies concealed amongst grass, &c. Several remarkable varieties in the form 

 of the cephalothorax in species belonging to the genera Walckenaera, Nmem, &c., 

 were mentioned, details respecting which will be found at length in the second 

 part of Mr. Blackwall's work on our native species, shortly to appear under the 

 auspices of the Ray Society. The exti-aordinaiy difference in size between the 

 males and females of many spidei-s was alluded to : in some, as the Diadem-spider 

 of oiu" gardens, the female is three or four times as large as the male, and powerful 

 in proportion; waywai'd and capricious, she is apt to seek to enjoy by making a 

 meal of him, hence the disproportionate length of the limbs. Some spiders, how- 

 ever, especially amongst the smaller species, are gregarious and social. 



Many other interesting circumstances respecting spiders might have been men- 

 tioned but for the fear of taking up too much time ; as the habits of Argyroneta 

 aquatica, which, though an air-breathing spider, lives habitually in water, cairying 

 an extempore diving-bell about with it, and forming a habitation by imprisoning 

 air at the bottom of the water by fine silken lines. The power of restoring ampu- 

 tated limbs, of sustaining entire abstinence fi'om food for very lengthened periods, 

 the probable duration of life, the gi-aceful form of the cocoon.s, were pointed out aa 

 well worthy of attention. 



Some interesting facts respecting the spiders found in coal-mines were then 

 alluded to. Some months ago it was publicly stated that'spiders' webs occurred in 

 the abandoned workings of the Pelton CoUieiy, near Chester-le-Street, county of 

 Durham ; specimens of the architects of these webs, on being submitted to careful 

 examination, proved to be Nei-mie errcms, a small spider met with occasionally 

 about the time of the hay-hai-vest. It appeal's prooable that some individuals 

 were carried down into the pit with the provender for the hoi-ses, of which about 

 seventy are constantly employed in the workings. There they have bi-ed freely. 

 Mr. West found their cocoons in great quantity on the roof of the working, and 

 obtained some little insight into the nature of their food by finding entangled in a 

 portion of web, a specimen of the brown plume-moth, one of the midges, and a 

 number of serrate hairs from a hairy caterpillar. The special point of interest, 

 however, is that with altered circumstances a modification appears to have taken 

 place in the instincts of these spiders. In their natural state they are only Imown 

 as solitary wanderers, making no web of any kind, further than a few scattered lines. 

 Have their instincts so changed by scantiness of and difficulty in securing prey that 

 in the coal-mine they become gregarious, and live in large colonies ? from being 

 neither spinners nor weavers, they take to constructing sheets of web of compara- 

 tively va.st size. Mr. West saw one 30 feet long by 4 feet 6 wide, hanging from 

 about the middle of the roof; and Mr. David P. Monison, who lives at Pelton, and 

 was the first to carefully observe them, has recorded the occurrence of many nearly 

 as large. Is any alteration in the structure of the spiders taking place ? Are the 

 optic nerves becoming atrophied, the number of the spinnerets increasing, and the 

 glands secreting the silk increasing in size ? Here is a fine opportunity afforded 

 for practically testing Mr. Darwin's theoiy of the origin of species, since we know, 

 from the time the pit has been worked, that it cannot be long since the first indivi- 

 duals were taken undergTound, Will the naturalists who may follow us have the 



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