TRAP-DOOR SPIDERS. 75 



structure of these fabrics. Thus, for example, the 

 dwellings of only eight out of the thirty-six species 

 of trap-door spider stated by Prof. Ausserer* to be- 

 long to the Mediterranean region are known in books, 

 those of the remaining twenty-eight being, as far as 

 I have been able to learn, yet to be discovered. This 

 is the more strange as from the nocturnal habits of 

 these creatures it is almost always necessary to dig 

 them out of their nests ; indeed it is more than pro- 

 bable that if all the dwellings which have been de- 

 stroyed had been described, the following pages would 

 never have appeared. 



Before proceeding to pass briefly in review what 

 has been written on the subject of trap-door spiders, 

 it will be w^ell to take one glance at the relation which 

 these spiders bear to their fellows. The great order 

 of spiders {Aranece) has recently! been divided into 

 seven sub-orders, the fourth of which, Territelaria, 

 includes all the trap-door spiders, and some others 

 which do not construct trap-doors. This sub-order 

 corresponds with that which was formerly called 

 Mygalidce, but this name, as well as that of Mygahy 

 originally given to all trap-door spiders, has been 

 abandoned because this latter name had previously 

 been applied to a genus of Mammals, and it was 

 feared that confusion might arise. 



The Terriielarice [or underground weavers] are dis- 

 tinguished from all other spiders by the position of 



* Prof. Ausserer (Anton.), Beitriige zurKenntniss der Arachniden Familie 

 der Territelarise (Mygalidae), iu Verhandlungen der k.k. Zool. But. GescU- 

 schaft in Wien. Jahrg. 1871, Band xxi. 



t Thorell, On European Spiders, in Nova Acta Reg. Soc. Scient. Upsa- 

 liensis, ser. iii. vol. vii. fasc. 1 and 2 (1869-70). 



