and (Economy of the Araneidea. 229 



Another male Tegenaria civilis, after nndergoing the same treat- 

 ment exactly as that in the preceding experiment, was introduced, 

 on the 6th of May 1842, to a female of its own species, which had 

 been in solitary confinement from the 25th of January 1840, and 

 had cast its skin three times during its captivity. This female re- 

 ceived the embraces of the male as soon as he was admitted into 

 the phial to her, and laid a set of eggs on the 27th of the same month, 

 all of which were productive, the young beginning to be disengaged 

 from them on the 27th of the ensuing month. 



In stating a further repetition of this experiment with spiders of 

 the same species, it is only necessary to premise that the female had 

 cast her skin three times in captivity, and that the male had but the 

 right palpus, the other having been removed by amputation. They 

 were placed together on the 16th of May 184-2, paired the same day, 

 and were separated as soon as their union was accomplished. On 

 the 19rh of June the female deposited a set of eggs in a cocoon, 

 which began to be hatched on the 24th of the following July, and 

 all produced young. Without further sexual intercourse, in 184-3 

 she enveloped a set of eggs in a cocoon on the 7th of April, the 5tli 

 of May, the 1st of June, the 18th of June, and the 3rd of July, re- 

 spectively, from all which young were disengaged. 



Promptness in accommodating itself to the restraint of confine- 

 ment, together with the certainty of being able to procure specimens 

 whenever they might be required, led to the selection of Tegenaria 

 civilis as a suitable subject for the foregoing experiments, from which, 

 conjointly with the preceding observations, the following inferences 

 may be deduced : — 



1st. That female spiders are incapable of producing prolific eggs 

 without sexual intercourse. 



2nd. That females which have not been impregnated occasionally 

 produce sterile eggs. 



3rd, That the female of Tegenaria civilis, when impregnated, is 

 capable of producing several sets of prolific eggs in succession with- 

 out renewing its intercourse with the male*, two years or more oc- 

 casionally elapsing before all are deposited, and a period of ten 

 months nearly intervening sometimes between the deposition of two 

 consecutive sets. 



4th That spiders of various species copulate without the abdo- 

 men of the male being brought into contact with that of the female. 



5th. That male spiders, in which the part, stated by Treviranus 

 to be the seat of the sexual organs, is entirely covered with strong, 

 well-gummed writing paper closely applied, nevertheless possess the 

 power of exercising the function of generation unimpaired. 



6th. Lastly, that males so circumstanced invariably consummate 

 the act by applying the palpal organs to the vulva of females, plainly 

 demonstrating thereby the interesting truth, that those organs, 

 however anomalous their situation may be, are the only efficient 



* Tegenaria domestica {Aranea domestica, Linn.), Agelena labyrinthica, and 

 Epeira cucurbitina are endowed with similar powers of production. Vide the Re- 

 port of the Third Meeting of the British Association, p. 4-13. 



