82 THE NATURE STUDY COURSE. 



Some spin circular webs, others sheet webs, others funnel- 

 shaped webs, and some do not make webs of any kind. Some 

 kinds spin their snares, then lie in wait for luckless insects 

 to be trapped ; others watch for passing insects and then 

 jump upon them. The spinners have usually three pairs of 

 spinnerets on the abdomen covered with numerous hollow 

 hairs. When they spin they exude through these hairs minute 

 streams of a fluid which hardens and compacts into a very 

 fine thread. Some kinds of spiders rise high in the air and 

 float or are blown along with the wind as far as they wish to 

 go. How can they perform this feat 1 To find out, fix a long 

 broom-straw by a cork into a small bottle filled with water. 

 Immerse the bottle up to or above the cork in a cup of water. 

 Set the cup in an open window, release a captured spider, 

 preferably of the smaller species, on the straw, and observe 

 it, after making repeated unsuccessful efforts to escape from 

 the base, ascend to the top and throw out a floater to carry it 

 off through the air. Infer how the spider can stretch his 

 web from tree-top to tree-top. If a spider is held by a 

 hind leg with a pair of forceps it will commence to spin a 

 thread which can be caught on a twig or straw and drawn out 

 under observation. 



Spiders' eggs are found in little silken sacs, a quarter to a 

 half incli in diameter, hidden under loose bark or among 

 stones, or hanging up in dark corners. These may be 

 collected in the fall and kept in a dry place in a shed or cool 

 garret until the spring. Then the capsule may be broken up 

 and the hatching process observed. Not so many spiders will 

 leave the box as there were eggs put in it because the 

 survivors make their start in life by eating the late comers. 



Compare the spider with the fly or bee as to means of 

 locomotion, and as to food and how each obtains it. The spider 

 has two main divisions of its body — cephalothorax and 

 abdomen; the fly has three— head, thorax and abdomen. 



