THE LIFE AND BEHAVIOR OF THE HOUSE SPIDER 



H. E. EWING. 



Few species of invertebrates come under our every day obser- 

 vation more than the common house spider, Theridion tepidario- 

 rum K. It is a familiar object in attics and in basements, in 

 cellars and in outhouses of all kinds, in fact it will be found in 

 almost any of the situations where there is shelter and moisture, 

 and where insects may be found in sufficient numbers for food. 

 In looking up the literature relating to this spider the writer was 

 surprised to find that no one, apparently, had worked out its 

 life history or made systematic observations on its Habits. 



In a casual way people have long observed some of the inter- 

 esting habits of the hoase spider, while its feats of bravery or 

 skill have occasionally attracted such attention as to elicit com- 

 ment from the press. Those who are interested in nature study 

 will find in this species a subject for observation fully as worthy 

 as the honey bee, the field mouse or the robin. 



It is believed that the house spider is an American species, 

 because on this continent it is frequently found out of doors 

 away from the habitations of man, while in Europe it is found 

 almost exclusively under artificial conditions. If this is time, 

 the semi-domestieation of this species must be of recent origin. 

 Because of the close relationship of this spider to man Professor 

 Comstock calls it the domestic spider, although it is probably 

 more frequently known as the house spider, 



LIFE ON THE WEB. 

 This spider is domestic in two senses of the word, it lives in 

 close relation with man, and on its web w'e find all individuals 

 of a home — male, female and offspring. The male, however, may 

 be only temporarily on the web, for he is more or less of a 

 wanderer, and if driven from his home by his domineering 

 spouse, he may hunt a more congenial mate elsewhere, or obtain 

 solace from a w^andering life of adventure. The young spiders 

 stay on the web of the parent for many days. Here most of 

 them either die of starv^ation, or become dainty morsels for the 

 mouths of hungry bird nestlings. 



Duties and Habits of the Female. The female spider (fig-ure 

 31) is much larger than the male and is iLsually about one-third 

 of an inch long, although individuals varv much in size. The 

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