890 



Rural School Leaflet 



SPIDERS 



Anna Botsford Comstock 



"^^^^-^N the opinion of some persons who are not in the 

 habit of counting what they see, the spider is an 

 insect. This is quite as absurd as caUing a rabbit a 

 bird; for any one not blind can see that the 

 spider has eight legs and the insect only six, and 

 that the spider has only two parts to its body, 

 while the insect has three — the head, thorax, 

 and abdomen; the spider has its head and thorax joined. More 

 than this, spiders never have wings. Spiders have two pairs of 

 jaws, similar to the jaws of insects, and in most cases they 

 work side wise instead of up and down as do our jaws. The 

 first pair of jaws is called the mandibles and the second pair, the maxillse. 

 Each of the inner jaws, or maxillae, bears a large feeler, called the 

 palpus. In some spiders these palpi are long, resembling legs, while in 

 the males the tip of the palpus is knob-like in form. 



The eyes of spiders are not like the large compound e3'es of insects. 

 They are single, each shining like a little gem, and are usually four in 

 number; however, there may be but two, or there may be six. 



The most interesting of the spider's organs are its spinnerets. These 

 are tiny organs at the tip of the rear end of the body, and on each spin- 

 neret are many tiny tubes, sometimes as many as two hundred and fifty, 

 each tube capable of spinning a strand of silk. The silken thread of the 

 spider is indeed most delicate, and yet each single thread is made up of 

 several strands. 



The spider's silk is of various kinds and is used for 

 various purposes, as follows: 



I. The silk is used to make a protecting sac for the 

 eggs. These sacs vary greatly in appearance. One is jug- 

 shaped and as large as a marble, and is suspended by 

 silk in the top of weeds; this is the sac of the large 

 yellow-and-black spider that makes its orb web in the 

 bushes in fields. Some spiders make globular egg sacs 

 and hang them on lines of strong silk in bushes; others 

 build soft, yellow, downy sacs under stones or boards 

 or in other protected places; while a very common 

 spider of our fields, which does not make a web at all, 

 spins a shining egg sac attached to stones. This sac is flat, circular, and 

 silvery in color and is not so large as a ten-cent piece. In all spiders' 

 egg-sacs there are placed many eggs, and in the case of some observed 



Egg sac of a 



common spider 

 found on stones 

 in fields 



