MIMICRY IN SPIDERS. 355 



case he observed that a new covering had been cleverly extemporized out 

 of three fallen olive leaves, taken from the vicinity, which were loosely 

 spun together and attached by one or two threads to the margin of the 

 tube. This formed an admirable concealment, but did not move freely 

 as a door, the web being too imperfect. Two days later, however, it was 

 completed, and had become a perfect door, moving on a hinge just within 

 and below that of the former door, which still remained as it had been 

 fastened. The other nests remained in the same condition as before, only 

 that a little moss had been dragged into the mouth of one tube, which had 

 been partially closed with its own lip.' 



Moggridge further states that Trapdoor spiders, Nemesia mcridionalis, 

 will make use of various objects strewed near their nests, in order to build 

 up a new door. This he tested by placing bits of scarlet braid 

 Objects ^^°"^ ^^^'^ particles of moss and fragments of leaves, in a circle 

 Taken.^ around the opening of the tube, and about two inches away 

 from it. Nevertheless, it is apparent that these Trapdoor spiders 

 do exercise some discrimination in the choice of materials, for Mr. Mog- 

 gridge observed several instances in M'hich, when the door of the cork 

 nest had been removed, if the door had been originally covered with moss, 

 it would again be used in its reconstruction, even though the mouth of 

 the tube were then surrounded by bare eartli. 



Thus, in reasoning upon the power of the spider to disguise the en- 

 trance to its habitation by mimicking surrounding natural objects, we are 

 brought in contact with this apparent defect of rational action. This point 

 Moggridge further illustrates by a case in which he had cut out a little 

 clod of mossy earth about two inches thick and three inches square on the 

 surface, containing the top of the tube and the moss covered cork door of 

 Nemesia cajmentaria. He found, on revisiting the tube six days later, that 

 a new door had been made, and that the spider had mounted up to fetch 

 moss from the undisturbed bank above, planting it in the earth which 

 formed the crown of the door. Here the moss actually called the atten- 

 tion of an observer to the trap, which lay in the little plain of brown 

 earth made by the digging. He subsequently saw many examples of the 

 same sort, and purposely removed several cork doors from mossy banks, 

 in order to observe this point. •^ 



If in the above cases the spiders appear to have been guided by the 

 simple wish to protect themselves with the first available material, in 

 _ other cases the mimicry seems to be duo to the natural secret- 

 SeCTet^^ iveness of animals seeking prey. Mr. Moggridge detected the 

 iveness. rem'^ns of insects, and especially ants, in the nests which he ex- 

 amined in situ. Frequently, however, one may open several in 

 succession without finding any of this debris, and at other times it will 



' Trapdoor Spiders, page 121. ■' Ibid., page 120. 



