Cambridge. — On the Spiders of New Zealand. 191 



good and tangible specific characters, most useful (in fact indispensable) in the 

 determination of species, in many cases where form, colour, aud other points 

 of structure present but little reliable difference.* In one instance {Lycosa 

 andrenivora, Bl.) I observed frequent acts of copulation (1) between an adult 

 male and female, and in every act there was an embrace which brought the 

 under part of the abdomen of each spider in contact with that of "the other, 

 forming a perfect apparent coition between the sexual apertures of the two ; 

 in this instance the palpi were not used at all. 



An eminent Prussian arachnologist (Herr Menge) has based numerous 

 genera on the form of the several portions of the male palpal organs ; but the 

 mere fact of these characters belonging to one sex only, appears conclusively 

 fatal to their adoption as leading characters of genera. The sjoinners of spiders, 

 situated as before observed (f. 2o, 15o, and 13r), are two, four, six, or eight 

 in number, and usually placed in pairs ; when a fourth pair is present it is 



* At the time of writing the above I had not had an opportunity of seeing two 

 papers by German araueologists, A. Menge (Ueber die Lebensw. d. Arachn., p. 36) and 

 A. Ausserer (Beob. ueber die Lebensw. der Spinnen, p. 194, etc.), in which, as quoted 

 by Dr. Thorell (" On European Spiders," p. 27, note 1), it is stated that "the male spider, 

 before the act of copulation, emits from the sexual aperture, situated under the base of 

 the abdomen, a drop of sperma on a kind of small web made for the purpose, which drop 

 he then takes up in the genital bulb of the palpi." 



If this be the usual modus operandi, it certainly seems strange that so painstaking 

 and accurate an observer as Mr. Blackwall should never have seen it take place during 

 at least forty years' observations "in the field." I certainly have not myself witnessed 

 any such process, though in some few instances the whole act, apparently, of copulation, 

 from its beginning to its conclusion, has come before me. Mr. Blackwall also, in a paper 

 just come to hand (Proc. Lin. Soc. , Vol. VII.), and entitled "A succinct review of 

 recent attenvpts to explain several remarkable facts in the physiology of Sinders and Insects," 

 alludes to Herr Menge's solution of the point in question, and also to a conjecture of 

 M. Duges, oifered many years previously ; and he mentions a fact observed by himself 

 in reference to a male of Agelena labyrinthica which seems to support a part both of 

 Dug^s' conjecture and Menge's solution. Mr. Blackwall says that "a male of Agelena, 

 labyrinthica, 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 sj)ider, by the alternate 

 application of its palpal organs, speedily imbibed the whole of it." 



Since the above note was peimed I have received the concluding part of Thorell's 

 " Synonyms of European Spiders,'' in which (Part IV., pp. 591-595) Dr. Thorell reviews 

 most of the above among other considerations upon this interesting subject. It appears 

 that a German araneologist, Herman, of whose writings I was ignorant, had in 1868 

 concluded that there was some communication by a di;ct, or ducts, between the spermatic 

 vessels in the abdomen and the palpal organs. This idea seems to be negatived by 

 former anatomists (Duges and others), who have failed to discover any duct in the palpus, 

 where it should, if existant, be of comparatively easy discovery ; but their failure to 

 discover more than two flexiiose vermicular spermatic vessels in the abdomen does not 

 couAance me that other— may -be excessively minute but efficient — ducts may not be there, 

 and so connect these tubes (through the stalk which contains the alimentary canal, and 

 joins the cephalo-thorax and abdomen) with the oesophagus, as mentioned above. 



