The iiKitlior «<)lf spider carries a silk-ei)\ ered mass ol eggs with lier, held hy her spinnerets, 

 until the young emerge. (Florida. Andreas Feininger) 



surface, the spider brings loads of air below the dome, 

 combs them olf as a series of bubbles, and goes above 

 the water again for a fresh cargo of gas. The air re- 

 leased under the dome accumulates as one big bub- 

 ble, and in this anchored diving hell the spider can 

 live well below the surface of the pond, sallying forth 

 at intervals to capture aquatic prey. 



The largest spiders, such as the bird spider Avic- 

 iiUiiia of South America and the false tarantula 

 Eiirypchna of the southwestern United States and 

 Central America, hunt chiefly at night by touch and 

 perhaps by hearing. They overwhelm their prey by 

 sheer strength, and often capture earthworms, mice, 

 and small lizards. Occasionally these spiders are car- 

 ried to big northern cities in bunches of bananas and 

 create a panic among fruit-handlers, who fear them 

 without real cause ( Plate 1 07 ) . 



Poison from the cheliceral fangs is the chief 

 weapon of smaller spiders. The venom is secreted by 

 large glands opening at the tips of the chelicerae. 

 making these appendages into efficient hypodermic 

 needles. The spider seizes a captive in the fang por- 

 tion of the chelicerae as though in a pair of ice tongs, 

 and injects a small amount of poison from each side. 

 The venom acts both as an anesthetic and as a di- 

 gestive juice of high potency. In a short time it lique- 

 fies the body contents of an insect. Then the spider 

 carefully inserts the fangs again and uses them as 

 drinking straws through which to suck out the liquid. 



These differences in habit related to size explain 

 why large spiders, like large scorpions, make interest- 

 ing pets and rarely use their venom. Their poison is 

 actually less virulent and cannot hurt more than a 

 bee sting. Smaller spiders and scorpions have a more 



potent poison, and a medium-sized individual may be 

 really dangerous. Actually man needs to fear only a 

 very few kinds. 



A spider whose venom has been fatal to fully 

 grown men on many occasions is the black widow, 

 Lalrodectus mactans (Plate 11.^). which occurs 

 from Canada to Tierra del Fuego. Its abdomen is al- 

 most spherical, glossy black, and as much as '2 of an 

 inch in diameter. Below the abdomen is a red spot 

 that may be hourglass-shaped or rectangular. Prob- 

 ably most bites from the black widow are suffered by 

 people who accidentally disturb a mother Latrodec- 

 tits in a privy or cellar corner where she is defending 

 her eggs in an irregular nest similar to that of the 

 house spider. The male Laimih'citc is much smaller 

 than his mate, as is usual among spiders, with a body 

 less than '4 of an inch long. He is harmless to man. 



The diminutive males of Ncphila and other orb- 

 weavers often make little webs of their own at the 

 periphery of the big web of their mutual mate. At in- 

 tervals they twitch the strands of the main web as a 

 courtship gesture. If the relatively huge female is well 

 fed. it is fairly safe for a male to approach her. Oth- 

 erwise she is likely to seize him as though he were a 

 fly, and digest the would-be suitor. 



Most spiders have eight simple eyes like bright 

 jewels around the forward portion of the cephalo- 

 thora.x — the leg-bearing subdivision o\ the body. The 

 arrangement of the eyes and their relati\e size differ 

 from one genus to another. Jumping spiders, such as 

 the little pepper-and-salt-colored Saliiciis. have one 

 pair of eyes enlarged enormously. With their help the 

 spider can gauge distance and identif\ pre\. abilities 

 demonstrated by frequent leaps to a small branch as 



245 



