NoVKMBEB 1, 1897.] 



KNOWLEDGE. 



251 



naturalists have visited this locality, but all have failed in 

 finding any specimens — and the male has not yet been 

 discovered. 



On January 29th, 1894, Mrs. Enoek was successful in 

 re -discovering the locality at Hastings and obtained 

 several specimens of the female — but the male of this type 

 still remains unknown. I have searched for it several 

 times from autumn to spring, but without success, so am 

 inclined to think that it may prove to be of a different 

 species to the Hampstead type, which is the subject of this 

 article. 



Mr. Brown, the original discoverer of our British repre- 

 sentative, just mentions that his " attention was arrested 

 by seeing something hanging down a bank which looked 

 like the cocoon of some moth." 



Never having seen either spider or nest, my only guide 

 was the above description, and for many months I was 

 constantly searching every bank which I happened to 

 pass. I had worked most of the likely lanes and banks in 

 the North of London without success, when I turned my 

 attention to that happy hunting ground, Hampstead 

 Heath, almost every inch of which I walked and worked 

 over. Until I had convinced the constables that I was not 



an escaped lunatic, 

 they continued to 

 watch me day after 

 day — much to my 

 amusement and 

 occasional annoy- 

 ance. However, all 

 this came to an end 

 before long, for in 

 one part of the 

 Heath at last "my 

 attention was 

 arrested by the 

 sight of something 

 hanging down, 

 which looked like 

 the cocoon of some 

 moth."' 



But now, with 

 the game before 

 my eyes, I might 

 not dig it up, as no 

 one at Hampstead 

 was allowed " to 

 disturb the soil." However, I had a friend with me, 

 who kindly covered my attack, so that in about an hour 

 I had managed to dig up a fine nest, containing a large 

 female trap-door spider — which was quickly transferred 

 to a tin bos, and the disturbed soil nicely smoothed over, 

 without further trouble or interference from anyone. At 

 a future visit I was enabled to dig up several other 

 specimens, some of which I sent to the Rev. 0. Pickard- 

 Cambridge, who kindly informed me that they could 

 not be identified '• without the mature male." 



Fig. 1 represents the nest of the British trap-door 

 spider, shown in section in the sandbank. The hole 

 is about five-eighths of an inch in diameter, and the 

 depth varies from nine to fifteen inches, running back- 

 ward and downward at an angle of about thirty degrees. 

 This burrow is the work of many years ; the first one, 

 excavated by the young spiderhng twelve hours or so 

 after it has left the maternal home, being but one inch 

 deep by one-sixteenth of an inch in diameter. 



As soon as the spider has determined upon a site for 

 its dwelling, it proceeds to excavate a hoUow by using 

 its jaws, carrying the sand between them until it has 



Fig. 1 



-Section of Nest of a British 

 Spider. 



burrowed down a sufficient depth. It then commences 

 to line the inside with silk, which it weaves all over 

 the sides until the top is reached, when it continues to 

 weave a silken tube, carrying it up against the side of 

 the bank and attaching the converging ends of the silk to 

 some grass stem or leaf. When this is accomplished the 

 spider proceeds to the lower end of the burrow, from 

 which she takes up a 

 mouthful of sand, and 

 reversing her position 

 she reascends with 

 her load. Arrived at 

 the aerial portion of 

 the nest the spider 

 drives both of its long 

 fangs through the 

 silken structure, and 

 then, pressing the 

 sand through the 

 meshes against the 

 fangs, it "pit-a-pats " 

 with its feet on the in- 

 side, and thus causes 

 the sand to adhere 



to the outside. This Fia. 2.— British Trap-door Spider (Female). 



is repeated until 



the whole of the aerial portion is sanded all over, the 

 resemblance to its environment being so exact that it is 

 not an easy object to detect at a glance. 



As soon as the spider has finished sanding the outside 

 she fixes silk to the inside of the aiirial part, then walks 

 down to the bottom of the burrow, and quietly rests with 

 the silken cords stretched from the tip of her spinneret 

 to the top of the burrow. These threads form a sort of 

 telephonic communication— the slightest movement on 

 the outside setting them in vibration, and intimating a 

 visitor outside. 



Fig. 2 delineates the female trap-door spider, which, 

 when full grown, is about five-eighths of an inch long, and 

 the same across the legs. A glance reveals the fact that 

 this is a very powerful spider, but unfitted for active 

 climbing, which is not indulged in at any time. The legs 

 are well formed and developed for assisting in the removal 

 of the sand, though the principal part of this operation is 

 performed by the huge jaws, which are most powerful 

 organs, each being terminated by a long and slightly 

 curved fang. Anyone who has examined the common 

 garden spider will know that it seizes its prey by opening 

 its jaws laterally {see Fig. 4), whereas in Atypus the jaws 



open vertically (aee Fig. 

 •5 ) . The reason for this 

 difference is apparent 

 when we consider the 

 different circumstances 

 (described in the second 

 part of this paper) imder 

 which the trap - door 

 spider obtains its food. 

 Fig. S is a present- 

 ment of the male trap- 

 door spider, a very differ- 

 ent animal to the female, 

 who never leaves her 

 n£st unless compelled 

 by force to do so. 

 Though one or two 

 males had been found in odd places since 1857, no 

 record of identification had been made ; and as these males 

 had not been found in nests or tubes, it was taken for 



-British Trap-door Spider 

 (Male). 



