Superfamily Argiopoidea 



than behind; the posterior median eyes are larger than the 

 lateral eyes; the anterior row of eyes is recurved, the posterior 

 row, straight or procurved. 



Three well-known species occur in the United States. 



Mangora gibberosa (M. gib-be-ro'sa). — The adult female 

 (Fig. 541) is from one sixth to one quarter of an inch in length, 

 the male is somewhat smaller. The cephalothorax and legs are 

 light greenish yellow; the cephalothorax has a narrow black stripe 

 extending from just behind the eyes back into the median furrow 

 and the legs are armed with prominent black spine-like hairs. The 

 abdomen is white, mottled with yellow and striped and spotted 

 with black. There are three longitudinal stripes on the hind half 

 of the abdomen; the middle one of these extends farther forward 

 than the others; and there are several oblique stripes or spots 

 on each side of the abdomen. The cephalothorax is swollen on 

 each side of the median furrow; this probably suggested the 

 specific name. The abdomen extends forward in a rounded point 

 above the thorax. 



This is a very widely distributed species. It is common and 

 makes its web among the stalks of grass and on low bushes. Its 

 web is surprisingly large compared with the size of the spider, 

 the orb varying from six inches to a foot in diameter; but it is 

 so delicate that it rarely attracts attention, even when the spider 

 is very common. The abundance of the spider is frequently 

 made evident first by the appearance of many individuals in the 

 sweeping net. The web (Fig. 542) is either horizontal or inclined 

 and although exceedingly delicate it is very elaborate in structure. 

 The hub is either finely meshed or nearly open, and is surrounded 

 by a notched zone of many turns. Occasionally the hub bears a 

 circular or disk-like sheet and the notched zone consists of many 

 turns of the thread (Fig. 543). The viscid spirals are closely 

 woven and are very numerous; and the number of the radii is 

 also large. The web figured was that of an immature male. 



1 have most often found the spider resting beneath the hub 

 of its orb; but in some cases I have found it in a curled leaf above 

 the web. If disturbed, when resting on its web, it darts to the 

 ground or runs quickly to a neighbouring leaf. In the North 

 the spiders mature early in August. 



Mangora placida (M. pla'ci-da). The adult is about one 

 sixth inch in length. The cephalothorax is brownish yellow with 



505 



