and (Economy of the Araneidea. 227 



the subject, which is very generally adopted, is opposed to that de- 

 rived from physiological facts by Dr. Lister and the earlier systema- 

 tic writers on arachuology, who regarded the palpal organs as strictly 

 sexual. 



Rejecting the opinion of Treviranus, Baron Walckenaer has given 

 his support to that entertained by Lister and the physiologists, having 

 endeavoured to establish its accuracy by pursuing the imperfect 

 method of investigation employed by the latter, which chiefly con- 

 sists in examining the condition of the palpal organs when applied 

 by male spiders to the vulva of females and carefully noticing the 

 changes they undergo ; but as it is possible that such females, should 

 they prove to be prolific, may have been impregnated at a former 

 period, and as other organs than those connected with the digital 

 joint of the palpi may have been instrumental in producing the result, 

 observations of this description appear to be quite inadequate to effect 

 the object proposed. 



An attempt to relieve the inquiry from objections so weighty is 

 recorded in the ' Report of the Third Meeting of the British Asso- 

 ciation for the Advancement of Science, held at Cambridge in 1833,' 

 pp. 44-4-5, and the result arrived at has a direct tendency to confirm 

 the truth of the opinion promulgated by Dr. Lister. Since that time, 

 researches in connexion with this subject have been greatly extended 

 and varied, and it is satisfactory to add, that they supply a body of 

 evidence which appears to be conclusive as to the agency of the 

 palpal organs. 



The following is a concise summary of the more important par- 

 ticulars elicited by this investigation. 



It is an admitted fact, that female Aphides, when impregnated, are 

 capable of producing females which, without sexual intercourse, are 

 prolific through several successive generations. In order to deter- 

 mine whether this is the case with spiders or not, young females of 

 the species Teyenaria domestica, Tegenaria civilis, Agelena laby- 

 rinthica, Ciniflo atrox, Drassus sericeus, Theridion quadripunctatum, 

 Segestria senoculata, &c., were placed in phials of transparent glass 

 and fed with insects. Most of these individuals remained in cap- 

 tivity from one to three years after they had completed their moult- 

 ing and attained maturity ; yet three only, an Agelena lahyrinthica, 

 a Tegenaria domestica, and a Tegenaria civilis, produced eggs, and 

 they proved to be sterile, though several of the others, to which adult 

 males were subsequently introduced, laid prolific eggs after coition. 

 It is worthy of remark, that the spiders which produced unfruitful 

 eggs deposited them in cocoons and bestowed the same care upon 

 them as if they had been fertile. 



This preliminary point being settled, attention was directed in 

 the next place to spiders in a state of liberty, when it was perceived 

 that the males of various species do not bring any part of the abdo- 

 men near the vulva of the females in the act of copulation, and that 

 this is the case with the Lycosm in particular ; for example, the male 

 of Lycosa lugubris, after having made the customary advances, 

 springs suddenly upon the back of the female with his head directed 

 towards her spinners and the anterior part of the inferior surface of 



