76 



equal, ommonly in two roivs of four each, the posterior one 

 longest, bent from the base towards the anterior one ; feet, com- 

 monly the first and second pair longest, or the second alone 

 longest. 



Habits. Araneides wandering after prey, making no web, 

 [444] but casting irregular threads ; cocoon flattened, usually 

 placed under leaves, watched by the mother till the young are 

 hatched. 



Remarks. Well was it remarked by Walckenaer, that a 

 subgenus so easily recognized as Thomisus is nevertheless ex- 

 cessively difficult to characterize. There is not one feature, 

 save the small size of the cheliceres, a secondary character, 

 which is not liable to vary in the different species, and yet, the 

 subdivision is a natural one. Nay, the subgenus Philodromas 

 which seems to correspond to my first tribe, the Depressas, 

 does not appear to be sufficiently characterized to be separated 

 from this, at least if my Thomisus vulgaris can be referred 

 to it. 



Section I. HETEROPODiE. Four posterior legs shortest. 



Tribe 1. DepresS/E. Legs very long, equal in thickness, 

 body flattened. 



1. Thomisus vulgaris. 

 PL 10, fig. 1. 



Description. Pale gray, abdomen with four impressed dots, 

 body flat ; legs with indistinct darker rings. 



Observations. This spider, commonly seen on fencing or 

 prostrate timber, like those of the same genus, moves sideways 

 and backwards, but it is much more active than T. celer. 

 When pursued by an enemy, like Attus and Epeira, it leaps 

 and hangs by a thread, which supports it in the air. 



Habitat. United States. 



[PI. 18, fig. 77, eyes. Legs arranged 2. 1. 3. 4. This spi- 





