Superfamily Argiopoidea 



They are usually found on or near the ground, where some of 

 them build sheet-webs; these are so delicate as to be invisible 

 except when covered with dew. 



Many species are found among dead leaves, in grass, and in 

 moss. The best way to collect them is by putting the material 

 in the midst of which they live into a coarse sieve and shaking 

 it over a sheet of cloth or paper. 



In the autumn many of the erigonids. become aeronautic 

 spiders, migrating by means of silken threads, which buoy them 

 up in the air and transport them long distances. 



The males of the Erigoninas are distinguished from those of 

 the Linyphiinae by the presence of an apophysis on the tibia of 

 the pedipalps. This apophysis is situated at the distal end of 

 the tibia, either above or on its external angle, and varies greatly 

 in form; it either projects or lies on the base of the tarsus. 



In the female, the palpi are without tarsal claws and the 

 epigynum is usually very simple, consisting of a small plate 

 without a projecting ovipositor. 



The subfamily is a very large one. Crosby ('05) enumerates 

 141 species representing 31 genera that have been described from 

 North America; and doubtless there are very many undescribed 

 species in our fauna. It is impossible in the present state of our 

 knowledge to give a key for separating the genera; although a 

 beginning has been made by Mr. Banks who has published ('05) 

 a table for separating the males. We must content ourselves, 

 therefore, with references to a few of the more common species. 

 The names used here are those used by 

 Crosby in his Catalogue. 



Ceraticelus fissiceps (Cer-a-tic'e-lus 

 fis'si-ceps). — These small spiders meas- 

 ure only one sixteenth inch in length; 

 their colour is light orange. A shield Fig. 5 go. cephalothorax 

 overs the greater part of the dorsal of ceraticelus fissiceps 

 aspect of the abdomen; this is darker than the remainder of the 

 abdomen. The head is black or dusky about the eyes; and has 

 a transverse furrow back of the anterior median eyes; this furrow 

 is shallow in the female, but very deep in the male (Fig. 380). 



This is a very common species; it is found on low bushes in 

 the summer, and can be obtained by sifting leaves in the winter. 



Ccratnclus Icetabilis (C. lae-tab'i-lis). — This resembles the 



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