INTRODUCING SPIDERS 5 



the pairing. These organs of the male, called palpi, have no internal 

 connection with the gonads of the abdomen, so the semen must be 

 transferred from the genital orifice to the palpi. To accomplish this 

 the male spins a little sperm web, deposits a small globule of semen 

 upon it, and then sucks it into the syringe in each of the palpi. The 

 female has developed in front of the genital pore paired pouches for 

 the storage of the semen, each unit of which is shaped to receive 

 the corresponding palpus of the male. 



Since spiders are solitary, predaceous creatures, the male runs 

 considerable risk in approaching his usually much larger mate, who 

 may be only hungry and not ready for mating. Some males are 

 killed because of early failure to diagnose the attitude of the female, 

 or, after being successful in their suit, of not leaving the premises 

 before the normal predatory instincts of the female again dominate 

 her. Various routines have been devised by different groups of 

 spiders to gain the recognition of the female and make possible a 

 transfer of the semen in relative safety. 



In the bodies of spiders are found clues that give considerable 

 insight into the racial history of the group. From lumbering ground 

 creatures have come fleet runners on soil and vegetation, and trapeze 

 artists that hang in midair on silken lines. In the variety and strange- 

 ness of their forms, spiders surpass all comparable invertebrate 

 groups. In color pattern, ornamentation, and brilliance they are on 

 a par with any of the insects. Indeed, the vaunted brilliance of the 

 morpho butterflies and of the birds of paradise is excelled by the 

 iridescent variety of the jumping spiders of the tropics. Only the 

 small size of spiders conceals their beauty and keeps them largely 

 unknown. 



Finally, it should be noted that spiders have attained their pres- 

 ent position without benefit of so-called intelligence. Endowed 

 with incredibly complicated instincts, the spinning creatures per- 

 form their marvels largely as automatons, and show only moderate 

 ability to break the bonds of their behavior patterns. The baby 

 orb weaver spins a perfect orb web soon after it leaves the egg sac, 

 and thereafter scarcely changes it, except in size, during its whole 

 lifetime. The mother spider encloses her eggs in a sac which, often 

 beautifully designed, advertises the species to which she belongs, 

 and then defends her precious burden against any assailant. Instinct 

 plays a large role in every action of the spider and is the guiding 

 principle throughout its life. 



