Araneae. 95 



is very similar in appearance to that of an Agelenid spider. The Table-case 

 Avicitlariidae live in hollow trees, under stones, or in burrows or °' ""'■ 

 natural hollows in the ground. The species which excavate a 

 burrow rarely close the entrance with a trap-door. 



The burrows of a South American species {Ephehopiin iiiurium), Wall-case 

 together with examples of the spider itself, are shown in Wall- ^°' '^' 

 case 7. Nests of the common bird-eating spider [Avicidaria 

 avicnlaria) of the north of South America, constructed in the 

 hollow trunk of a palm tree, and in the rolled-up leaf of a banana, 

 are also shown in this Wall-case, and specimens of the spider, and 

 also of other species of bird-eating spiders, are placed in Table- 

 case 22. 



Fam. — Gtcnizidae. 



In the Ctenizidae the feet are not furnished with apical tufts 

 or pads of hair. The chelicerae are furnished with digging 

 spines. 



On account of their neatness and of the ingenuity displayed 

 in their construction, the trap-door nests of these spiders have 

 long attracted attention. The nest takes the form of a long 

 tunnel in the ground, the interior of which is lined with 

 smooth silk, the entrance being often closed by a neatly 

 fashioned trap-door, the outer surface of which exactly matches 

 its surroundings, so that it is practically invisible when closed. 

 The spider often constructs one or more side chambers to 

 the burrow, and sometimes shuts them off from the main 

 part of the tunnel by additional trap-doors, thus ensuring a 

 place of refuge in case the outer door is forced by an enemy. 

 Some of the species, which do not close the entrance to the nest 

 by a trap-door, erect a turret of grass or small twigs, bound 

 together by web, around it. In some instances {Pseudidiops, etc.) 

 the trap-door spider constructs its nest on the trunk of a tree, 

 spinning a silken tube in the crevices of the bark, and overlaying 

 it with chips of bark and lichen, so as to strengthen its walls and 

 to conceal it from view (Table-case 22). Most of the spiders of 

 this family have the carapace and limbs smooth and polished, and 

 the abdomen clothed with short dense hair, so that uo impediment 

 is offered to rapid movement in the silk-lined burrow. 



Two burrows of a trap-door spider (Actinopiis tuallacci), from Wall-case 

 Brazil, are exhibited in Wall-case 7. In one of them the spider •'^°- "*■ 

 is cautiously raising the lid, on the watch for approaching prey. 



