FIELD BOOK OF INSECTS. 



down of the primary spiral which is shown as ending at /. 

 All of these threads consist of smooth, tough silk which is 

 not sticky. From this point on the spider uses the sticky 

 threads which constitute the real snare. All the details 

 of spinning the web vary but the putting in of first sticky 

 threads is very irregularly done. In the figure given here 

 it may be followed from m to n. From n she continued 

 in a regular spiral until the primary spiral of smooth silk 

 was reached. She then cut away the outer portion of the 

 primary spiral, so that she might have more room for the 

 snare. This process of cutting away the primary spiral 

 and putting in the sticky spiral is shown, in the fourth 

 figure, about half finished; and finally there is the complete 

 web with nearly all of the primary spiral removed. Nearly 

 every species has its own distinct way of making webs 

 and there are so many species of this family which are 

 commonly noticed (especially the females when they are 

 swollen with eggs) both because of their beautful colors 

 and of their interesting webs, and some of the species are 

 so variable, that not all of the probable questions can be 

 answered. The spider an inch or more long, marked with 

 spots and bands of bright orange and usually seen in the 

 late summer hanging on an orb which is decorated with a 

 zig-zag band of silk is Miranda aurantia, also called Ar- 

 giope riparia. A slightly smaller, light yellow spider with 

 narrow transverse black lines on its abdomen is Metar- 

 giope trifasciata and also puts a zig-zag in its web. Some 

 species (Micrathena gracilis is shown in Plate VII) of this 

 family have spine-like processes on their abdomens but 

 Aranea is a fairly safe generic name to give to most of the 

 orb-weavers generally noticed. 



The THOMISID.*:, or crab-spiders, have the two front 

 pairs of legs relatively heavy and long; they run sideways. 

 They spin no snare and the white or light yellow, some- 

 times with a light red band on the sides, Misumena valid 

 (see Plate VII) is frequently seen sitting in flowers, 

 concealed by its resemblance to the flower and waiting 

 to catch the insects which come for pollen. The flat, 

 lustrous, parchment-like egg sacs often observed on stones 

 in pastures belong to Castianeira descripta, one of the 

 CLUBIONID^E. Agelena ncevia is responsible for the flat 



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