Superfamily Argiopoidea 



Genus METACYRBA (Met-a-cyr'ba) 



The cephalothorax is low and flat; it is broadest in the middle 

 and narrowed both in front and behind. The tibiae of the first 

 legs are armed with one or two short spines, or none at all, beneath. 

 The sternum is much narrowed in front between the anterior 

 coxae and widened behind. The ocular quadrangle is wider than 

 long. 



Only a single species is known. 



Metacyrba tceniola (M. tae-ni'o-la).— - This is a flat, nearly 

 black species. The males are a little less than one fifth inch in 

 length; the females, a little more than one fourth inch. The 

 cephalothorax is black, smooth, and without markings or with a 

 white line around the margin. The abdomen is dark gray, with 

 two longitudinal narrow lines of white hairs more or less broken 

 into short bars. The femora of the first legs are flattened and 

 much stouter than those of the other legs, especially in the males. 



This species is distributed throughout the United States and 

 is found also in Mexico. 



Genus M/EVIA (Mae'vi-a) 



The cephalothorax is rather high, with the sides nearly 

 vertical, and nearly parallel in the head region and slightly 

 rounded in the thoracic. The ocular quadrangle is slightly wider 

 in front than behind and occupies less than one half of the length 

 of the cephalothorax; the anterior eyes are in a straight or slightly 

 recurved line; the second row of eyes is nearly midway between 

 the other two rows. The legs are slender. The sternum is long, 



narrow in front, the coxae of the first legs 

 being nearly contiguous. The lower margin 

 of the furrow of the chelicerae is armed with 

 a compound tooth (Fig. 761). 



As now restricted only two species of 

 this genus occur in our fauna, M. poultonii 

 from Texas and Arizona, and the following. 

 Mcevia vittata (M. vit-ta'ta).— - This spe- 

 F 'g- 761. cies is of especial interest on account of a 



CHELICERA OF M/FATA ... ,. ,. f ., . ., . ., , 



vittata striking dimorphism of the male; it is a widely 



distributed and very common one. 



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