28 



AMERICAN SPIDERS AND THEIR SPINNINGWORK. 



Male 

 Organs. 



portion of the abdominal cavity, are seated in the central and posterior 

 part. The intestinal tube runs through it in nearly a straight direction 

 from the base to the aex, and the sacs and tubes which elaborate the 

 material for forming the webs are placed in the lower, lateral, and anterior 

 parts. In the male, the organs for the secretion of seminal fluid consist 

 of two long, narrow, convoluted tubes, occupying the same relative posi- 

 tion as the ovaries in the female. They also open outwardly into the 

 minute orifice noted above. 



The manner in which the act of pairing between the sexes occurs is a 

 matter of doubt, and probably diifers among different species. Mr. Cam- 

 bridge l reports a case in which a perfect apparent coition was 

 effected between sexual apertures of the male and female spider, 

 the palpi not being used at all ; and I have observed what 

 seemed to be a similar act in the pairing of the sexes of Agalena nosvia. 

 On the other hand, it is evident that the spermatic fluid is conveyed to 



the female parts of gener- 

 ation by the male palpi. 

 I have seen and recorded 

 this action in the case of 

 Linyphia marginata. Menge 

 and Ausserer have observed 

 that the male spider before 

 the act of union emits from 

 the sexual aperture a drop 

 of sperma on a web made 

 for the purpose, which drop 

 he then takes up in the 

 genital bulb of the palpi and then communicates it to the female. 



With regard to the function exercised by the remarkable organs con- 

 nected with the digital joint of the palpi of male spiders, there exists some 

 difference of opinion. Taking anatomy as his guide, Treviranus 

 Digital arr i ve (i a t the conclusion that the parts in question are used for 

 p , . the purpose of excitation merely, preparatory to the actual union 

 of the sexes by means of appropriate organs situated near the 

 anterior part of the inferior regions of the abdomen. This view of the 

 subject, which is very generally adopted, is opposed to that derived from 

 physiological facts by Dr. Lister and the earlier systematic writers on 

 arachnology, who regarded the palpal organs as strictly sexual ; and re- 

 cent researches, conducted with the utmost caution, have clearly established 

 the accuracy of the opinion advanced by that distinguished Englishman. 2 



FIG. 17. Collecting a spider in a box. 



1 For valuable anatomical notes sec his "Araclmida," Encyclopedia Britannica. 



2 Blackwall : "Reports 14th ^IcctiiiLr British Association Adv. of Sci.," pa^es <>7-(>'.. Also 

 ' Spiders of Great Brit, and Ireland," Introduction, page 5. 



