DEFENSES OF BURROWING SPIDERS. 



191 



scribed by Moggridge. Here we have simply a dropping away of 

 the turret of Dolichoscaptus, and the use of the burrow independ- 

 ently of the same, but with the 

 trap-door retained. In the spe- 

 cies studied by Moggridge a sin- 

 gle burrow is the ordinary rule ; 

 but there are many variations, 

 some of which are manifestly 

 characteristic of species, and 

 others which are probably occa- 

 sional and accidental. 



A variation described by Mr. 

 Simon is shown at Fig. 5, the 

 nest of Stothis astuta, which in- 

 habits the forest of Cartuche, 

 near Caracas, South America. 

 The drawing shows a section 

 of the burrow, indicating the 

 curved course, and also the two 

 wafer-like trap-doors habitually 

 placed at either end. That this 

 jjeculiar industry is defensive is 

 probable, for we can readily im- 

 agine the spider disappearing 

 within its den at one door, and, 

 if its pursuer should succeed in 

 entering the same, escaping at 

 the other. We might, without much stress of imagination, carry 

 the conception a little further, and suppose, again, the enemy mak- 

 ing its exit from one door and the spider again descending into 



its burrow by the other. This 

 game of bopeep might evi- 

 dently be played to the great 

 advantage of the trap-door 

 spider, and manifest discon- 

 certing of its enemy. 



Simon gives an interest- 

 ing example of the ability of 

 a spider of this species to 

 change its habit and adapt its 

 industry to unexpected sur- 

 roundings. The species com- 

 monly seeks dark and damp 

 localities, and digs in vegetable earth a burrow not very deep. 

 The nest was begun underneath a stone in soil which was so 

 rocky as to be impenetrable. Not wishing to change its site, and 



vlU 



Fig. 4. Turret, with Trap-dook, of Doli- 

 choscaptus latastei, supported on a plant 

 four inches high. (After Simon.) 



Fig. 5. Section View of Curved Burrow of 

 Stothis astuta, showing Double Trap-doob 

 Entrance. 



