158 ME. J. BLACKWALL OK SOME BEMARKABLE FACTS 



in numerous cases it ought to be very apparent, as the shortness 

 of the palpi would render a strong inilection of the cephalothorax 

 towards tlie inferior surface of the abdomen absolutely requisite 

 before they coukl be applied to the part indicated as the seat of 

 the seminal ducts. 



I shall conclude these remarks with the statement of a few facts 

 bearing upon the question, which have come to my knowledge in 

 pursuing researches relative to the generation of Spiders. 



In the act of copulation, the extremity of the organ of each 

 palpus of the male, in a state of tumefaction, is usually introduced 

 alternately into the vulva of the female, and that many times in 

 succession, without being once brought into contact with any part 

 of its own abdomen, though it is very frequently conveyed to the 

 mouth ; and I have observed a male Lycosa lugubris apply its 

 right palpus eighty times, in the manner above described, to the 

 vulva of a female (both of which had been placed in a clean glass 

 phial), without the possibility of bringing it into contact with the 

 inferior surface of its abdomen, except by a very conspicuous 

 change of position ; and as an equal number of similar acts were 

 performed by the left palpus, we have the extraordinary fact of 

 the palpal organs being employed 160 times during this greatly 

 protracted process, unaccompanied by any contact whatever with 

 the part where the seminal ducts are considered to terminate. 



A male Agelena lahyrintliica, confined in a phial, spun a small 

 web, and among the lines of which it was composed I perceived 

 that a drop of white milk-like fluid was suspended ; how it had 

 been deposited there I cannot explain, but I observed that the 

 Spider, by the alternate application of its palpal organs, speedily 

 imbibed the whole of it. Perhaps the only safe conclusion to be 

 drawn from this very remarkable circumstance, taken in connexion 

 with the previously well-ascertained ofiice of these parts, is that 

 it affords a complete answer in the affirmative to the question 

 asked by M. Duges, namely, " le conjoncture ferait-il alternativc- 

 ment I'office de siphon absorbant et d'organe ejaculateur ?" 



§ 3. 



My explanation of the means whereby various animals are sup- 

 ported in their movements on the vertical surfaces of liighly- 

 polished bodies having recently been called in question,'! am in- 

 duced to offer a few remarks in vindication of its accuracy. 



Mr. Tiiften West, in treating " On certain Appendages to the 



