139 



disappeared. A third one Avas found dead in the web of a 

 Tlieridion vidgare, which no doubt had killed it. A fourth one 

 was found eating that very same Theridion. This shows that 

 these two species are mortal enemies. I never knew a spider 

 of this species to remain more than two days in the same place. 

 Its habits seem to be nocturnal ; for generally, when discovered 

 in the day-time, it is found in some dark corner, or crevice, 

 with its legs folded in the manner of several species of Epeira. 



I sometimes enclosed specimens of this spider-eater with 

 other species of Araneides, in a glass jar, in order to watch its 

 motions. The moment another spider was thrown in, it showed 

 by its attitude that it was conscious of the presence of an 

 enemy. It first moved its first and second pairs of legs up and 

 down ; then slowly approached its victim, and generally killed 

 it. A Theridion vulgare, thrown in, manifested great terror ; 

 but after some seeming reflections on fortitude and necessity, 

 it prepared for the mortal combat, and cautiously advanced 

 towards the Mimetus, which moved more slowly. The Therid- 

 ion, when near, threw out a long thread, on which were sev- 

 eral globules of a transparent fluid. This partially succeeded, 

 for the Mimetus was caught by one leg ; and while the 

 Theridion retreated for observation, it was confined, and 

 dragged a.bout for a long time, before it succeeded in freeing 

 itself. The battle presently was renewed, and this time the 

 Theridion was conquered, and eaten. 



Habitat. Alabama. [34.] 



[PI. 18, fig. 33, eyes ; pi. 19, fig. 127, cocoon. Legs arranged 

 1. 2. 4. 3. Supplement.'] 



2. Mimetus tuberosus. 



PI. 15, fig, 14. 



Description. Pale or livid green ; cephalothorax with a black 

 mark branching out towards the eyes ; abdomen subconical, 

 with a tubercle near each of the anterior angles on the side, 

 disk brownish, obscure, with pale spots and a serrated black 



