48 AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



upwards and downwards, a movement which often may be observed in 

 males, and which gives an idea of an expression of impatience. 



The next observation, after a few minutes' absence, showed the male 

 about two inches behind the female, standing as it were on tiptoe. His 

 palps were placed alternately and nervously to his maxillae. On their re- 

 moval the whole body was raised still higher, and the abdomen 

 Palps! brought nearly to a right angle with the cephalothorax, with con- 

 siderable muscular effort in the basal portion, and with violent 

 tremulations. The movements, which were repeated four times, had the 

 effect of throwing the spider slightly forward, while the palps were 

 shaken in that peculiar manner which denotes great muscular tension in 

 some other part than that in visible motion. The palps were now gener- 

 ally alternately placed under the sternum and moved backward and forward, 

 upward and downward, with a scooping motion. In five minutes these move- 

 ments of the abdomen and palps were repeated ten times in regular succes- 

 sion, only varied by an occasional transfer of the digital organs to the 

 mouth. 



Mr. Campbell observed thirteen couples pairing in confinement from the 

 middle of July to the end of August; and the following account may be 

 Ap- teken as *yP ical of the species, with the exception that the union 



proaches. does not necessari ly occur so quickly after the female has gained 

 maturity. On the 13th of August he placed together a male and 

 female. On the 17th 'the latter cast her last skin. Up to that time, 6 A. M., 

 they had taken no notice of one another. At 9.45 P. M. the two were so 

 close together that the femora of the first pair of legs of each were 

 almost in contact. After a few convulsive twitches of the legs the male 

 pressed forward, moving his palps up and down, when, as they touched the 

 palps of the female, the pair played with these organs like two friendly 

 bees with their antennas. After a few minutes the female raised herself, 

 leaning a little on her left side, and the male crept forward until his head 

 was under the sternum of his mate, while his first pair of legs were rest- 

 ing upon hers. He then advanced his right palp, leaning a little to the 

 left, and using the left palp as part of his support. 



The male now rapidly raised his palps up and down for four or more 

 seconds, and with such energy as to compel the female to assume a verti- 

 Use of al P sition - He then retired, and again approached her, repeat- 

 Palps. lng the movements a greater or less number of times, occasion- 

 ally pausing before he withdrew his palps with a slight twist 

 At times he would leave the female for five minutes, and strut 

 with straightened legs around the vase, wagging his abdomen. Now and 

 then lie would remain perfectly still with the palp withdrawn, or play with 

 e palps of the female, who seemed in a comatose state. He would then re- 

 new the union with undiminished vigor, appearing on each occasion less 

 desirous of changing his position. 



