Superfamily Argiopoidea 



In this form there is on the middle line at the base of the abdomen 

 a three-lobed spot resembling, somewhat, a shamrock leaf; in front 

 of each of the four muscle impressions there is a white spot, and 

 there is a third pair of spots farther back and in line with these. 

 On the middle line of the abdomen there may be a row of spots; 

 these are sometimes represented by minute dots, or may be want- 

 ing. In addition to these markings there may be a variable 

 number of spots about the margins of the dorsal surface of the 



Fig. soi. ARANEA TRIFOLIUM, FEMALE 



abdomen. As a rule the folium is not outlined except in young 

 individuals; sometimes, however, it is well-marked (Fig. 502); 

 this form resembles the spectacled variety of the preceding species; 

 but it can be distinguished by the markings of the lower surface 

 of the abdomen, and, more surely, by the form of the epigynum. 



The ventral surface of the abdomen is darker than the dorsal 

 and usually lacks the semicircular yellow spots so prominent in 

 A. gigas and in certain other species. 



The epigynum (Fig. 503) differs markedly in form from that 



480 



