50 AMERICAN SPIDERS 



a few weeks most of the males disappear and gravid females are 

 found on all sides, some spinning up domiciles for egg-laying, while 

 others, having already made their first sac, carry it attached to their 

 spinnerets or held in their jaws. By midsummer the possibility of 

 finding males of the spring spiders is not very good, but the females 

 carry on far into the year, often laying several egg masses. Thus, 

 in the spring and early summer we have the males and females of 

 the spring fauna, and the juvenile and growing representatives of 

 the fall fauna. 



In the fall, the sedentary spiders advertise their presence in a 

 conspicuous manner by great sheet webs and expansive orbs. The 

 males appear in midsummer and early fall and attend the females 

 on the outskirts of their modest webs. In August we find the webs 

 of the grass spiders on grass and shrubs, and can surprise the adults 

 pairing in the funnels. The orb weavers now are attaining maturity 

 in great numbers, and every suitable situation is filled by a web 

 of variable dimensions. Having vastly increased in size, they spin 

 correspondingly larger webs. As the season progresses, the males 

 dwindle rapidly; soon all are gone, having lived the shorter, intenser 

 life identified with their sex. The females lay their eggs and enclose 

 them in sacs of various kinds, which tend to be more substantially 

 built and more heavily insulated than those of the spring spiders. 

 After the killing frosts of November, most adults of the fall fauna 

 are gone, but already the growing young of the spring spiders have 

 attained nearly their full development. During October and Nov- 

 ember, the partially developed spring spiders engage in ballooning 

 activities in company with many precocious fall spiderlings. The 

 fall spiders produce their eggs in the fall, and their young either 

 spend the cold winter months in their cocoons, or, having deserted 

 them, live under debris or in protected places until warmer days 

 allow them to begin their march to full maturity. 



It must not be thought that the two faunas are discretely sep- 

 arated one from the other. Actually they are bridged by species 

 that mature during the midsummer. Because of multiple cocooning 

 and precocity, or tardiness, of some species, there is a considerable 

 overlapping of the faunas. Further, some species do not seem to 

 conform to any definite pattern, and mature males and females may 

 be found during almost any month of the year. In the American 

 South it is possible to have two full generations during the year. 

 For the most part, however, even in warmer areas we find only 

 one generation each year. Over much of Canada there is only one 



