TRAP-DOOR SPIDERS. S4S 



however, though, the spider appeared in perfect 

 health. 



Neither this spider nor the true N. ccementaria of 

 Montpellier appears to have any idea of digging a hole 

 when placed on soft earth if they are adult ; and the 

 same thing is true of N. ManderstjerniB and N. Elea- 

 nora, but the young of all these spiders readily ex- 

 cavate nests for themselves. 



I have once seen a nearly full grown, and probably 

 adult, Cieniza Mog(^ndgii make a perfect tube and 

 furnish it with a moveable door in a single night 

 when confined under gauze on moist earth, but this 

 is the only instance (except that of Cteniza Calif ornica, 

 recorded above) in which I have known an adult trap- 

 door spider excavate or attempt to do so. 



These Ctenizas seem to be peculiarly able to adapt 

 themselves to circumstances, for two young ones, 

 which I sent by post to M. Lucas at the Jardin des 

 Plantes in Paris in little wide-mouthed, cylindrical, 

 blue glass bottles, not only lined the bottles with 

 silk but also closed them at the mouth with a door 

 fitting accurately into a bevelled lip, in the manufac- 

 ture of both of which fragments of moss, the only 

 material at their disposal, were used in place of 

 earth.* It is curious to see how quickly the young 

 trap-door spiders, both of the cork and w^afer kinds, 

 when taken from the nest of the mother, will make 

 their own perfect little dwellings in captivity, and I 

 have known them construct tube and door within 

 fifteen hours. 



* M. H. Lucas, in Bull, des Stances de la Soc. Entom. de Fr. No. 27 

 (1874), p. 101. 



