Superfamily Arglopoidea 



the middle of the abdomen where H. pikei has dark brown, 

 the female is known. 



Only 



Genus MARPISSA (Mar-pis'sa) 



The first pair of legs are slightly stouter than the second 

 pair and are armed with three pairs of spines beneath the tibia. 

 The abdomen is marked by an angular central band. The genus 

 is represented by three species in this country. 



Mar pis sa undata (M. un-da'ta). — This is a common species 

 in the eastern half of the United States and is found as far west 

 as Utah. It measures from .38 to .42 inch in length. The dorsal 

 aspect of the cephalothorax is of a uniform gray; and there is a 

 wide gray band with indented margins along the middle of the 

 abdomen (Fig. 749); this band is bordered with black. 



Fig. 74g. 

 MARPISSA UNDATA 



Fig. 750. 

 MARPISSA MELANOGNATHUS, MALE 



Marpissa califomica. — This species occurs in the Far West. 

 It is smaller than M. undata and has a wide gray band, bounded 

 by dark brown on the cephalothorax. 



Marpissa mclanognathus (M. mel-a-nog'na-thus). — This 

 differs from the other two species in having a white band bounded 

 by dark rufus on the cephalothorax. In the male the abdomen 

 has bright rufus bands in the middle and on the sides, alternating 

 with two longitudinal white bands (Fig. 750). In the female 



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