COURTSHIP AND MATING 73 



same, but hold the globule and the tiny web between the palpi or 

 front legs until it is absorbed. A great many spiders spin a tiny 

 sheet of very fine web, usually quadrangular or triangular in outline, 

 place a drop upon the surface, and then take the semen indirectly 

 by applying their palpi on the opposite side of the sheet. 



Among the tarantulas sperm induction is a long operation that 

 sometimes requires three or four hours. The male spins a large flat 

 sheet of silk, attached to adjacent objects, in which are left a large 

 oval opening and a much smaller one, the two separated by a nar- 

 row band of strongly woven silk. He then crawls through the large 

 opening, and, lying on his back, strengthens the silk around the 

 holes. After rubbing his palpi through his chelicerae and stroking 

 his genital opening against the reinforced silk band between the 

 holes, a drop of spermatic fluid appears and is deposited on the 

 underside. The male now clambers back, and, sitting upright on the 

 web over the globule, reaches around the edge of the narrow band 

 to touch the sperm directly. The process of absorption takes an 

 hour or more, and consists of a rhythmical alternate tapping of the 

 palpi in the globule, usually at the fast rate of one hundred to one 

 hundred fifty per minute. Afterward the web is destroyed or de- 

 serted. 



Most spiders are able to recharge their palpi much more quickly, 

 usually within half an hour. T. H. Montgomery has described how 

 one of the small American wolf spiders, Schizocosa crassipes, spun a 

 triangular sheet attached to the floor and walls of its cage, and stood 

 on the upper side of this web. A small globule of yellowish semen 

 was ejaculated upon the surface of the sheet at about the middle. 

 The male "then reached his palpi downward and backward, below 

 the sheet, and applied the concave portion of the palpal organ of 

 each against that part of the sheet which carried the drop of sperm. 

 Each palpus was then rubbed against the lower surface of this drop 

 several times, then withdrawn and slowly shaken in the air, while 

 the other was similarly applied to the drop." 5 This process con- 

 tinued for seven minutes, during which time all the sperm was taken 

 up into the palpal organ, and soon afterward the male left the sperm 

 web. 



The male seems to derive considerable gratification from the 

 process of sperm induction. Before the act, the genital region is 

 rubbed against the strands of webbing to incite the ejaculation of 



$ T. H. Montgomery, "Studies on the Habits of Spiders, Particularly Those 

 of the Mating Period," Proc. Acad. Nat. Set., Philadelphia, 1903, p. 65. 



