228 Mr. J. Black wall on the Structure, Functions 



the abdomen resting upon her cephalothorax ; then placing the first 

 pair of legs immediately behind her posterior pair, the second pair 

 between her second and third pairs, the third pair between her first 

 and second pairs, and the posterior pair before her first pair, he thus 

 embraces her, and applies the palpal organs to the vulva by inclining 

 to one side or the other as the occasion may require. In this situ- 

 ation the male remains till the act of union is consummated and 

 then quits it with precipitancy, so that his abdomen is not even 

 brought into contact with that part, much less with the vulva, of the 

 female. 



Precisely the same manner of proceeding is pursued by Lycosa 

 agretyca^ Lycosa saccata^ Lycosa pallida, and Lycosa obscura ; and 

 females of the last species have been seen to receive the embraces 

 of several males in immediate succession, and to copulate even at the 

 time they had cocoons containing newly-laid eggs attached to their 

 spinners, which circumstances serve to support the opinion that 

 some spiders pair oftener than once in the course of their lives. 



When in captivity, the sexes of Lycosa lugubris sometimes con- 

 tinue paired more than four hours, during which period the male 

 applies the palpal organs several hundred times to the vulva of the 

 female. 



Notwithstanding the important bearing of these observations upon 

 the physiological problem under consideration, something was still 

 wanting to complete its solution, and recourse was had to direct ex- 

 periment to supply the desideratum. 



On the 4th of May 184?2, an adult male Tegenaria civilis was pro- 

 cured, and, being held by the legs in an inverted position, the in- 

 ferior surface of the abdomen was moistened by applying to it a 

 camel's hair pencil which had been dipped in water. The entire 

 interval between the plates of the spiracles, supposed by Treviranus 

 to be the seat of the sexual organs in male spiders, and even a con- 

 siderable space below that interval, was then covered with strong, 

 well-gummed writing-paper cut into a suitable form and closely ap- 

 plied, and when the paper became thoroughly dry and firmly at- 

 tached, the spider was placed in a phial with a female of the same 

 species, which had been in solitary confinement from the 2nd of 

 June 1841, and had cast its skin twice during its captivity. With 

 this female the male paired on the same day he was introduced to 

 her, applying the palpal organs to the vulva in the usual manner, 

 and immediately after the union was completed he was removed from 

 her. On the 23rd of May she deposited a set of eggs in a cocoon 

 spun for their reception, and on the 11th of June she constructed 

 another cocoon in which she laid a second set of eggs. All these 

 eggs proved to be prolific, the extrication of young spiders from the 

 first set commencing on the 26th of June, and from the second set on 

 the 13th of July, in the same year. Without renewing her inter- 

 course with the male, this female deposited a set of eggs in a cocoon 

 on the 2nd of April, the 9th of May, the 4th of June, the 22nd of 

 June, and the 9th of July 1 843, and on the 22nd of April, the 30th 

 of May, the 29th of June, and the 1st of August 1844, respectively, 

 nine sets in number, all of which produced young. 



