208 Proceedings of the Royal Irish Academy. 



The cMef interest to be deriyed from sucli a list as the foregoing 

 lies in. the allocation of the various species to their faunistic types. 

 The importance of Ireland and its fauna from a distributional stand- 

 point has been lately brought home to naturalists by my friend 

 Dr. Scharff, in whose Paper^ the various divisions of our animal 

 population are fully discussed. There is difficulty in dealing with 

 the spiders from this point of view, because their distribution is as 

 yet imperfectly known. It may be well, however, in concluding this 

 Paper to put forward a few suggestions, which subsequent knowledge 

 may confirm or modify. 



It is clear that a very large proportion of our spider population 

 belongs to that widespread faunistic group which ranges over vast 

 tracts of the Holarctic Eegion, and includes the most dominant and 

 vigorous members of our fauna. Segestria senoculata, Drassus lapi- 

 dosus, Cluliona terrestris, XysUcus cristatiis, Tegenaria domestica, 

 Theridion lineatum, Erigone dentipalpis^ Linypliia triangularis, Pachy- 

 gnatlia Degeerii, Meta segmentata, M. meriancB, Araneus diadematus, 

 A. cornutus, A. quadratiis, Lycosa pidverulenta, Pirata piraticus, and 

 Pardosa ame^itata are a few typical examples of this group. Some of 

 them have a more or less restricted range in the British Isles ; Pisaura 

 miraiilis, for instance, which is found as far north as Trondjem in 

 Norway, seems confined to the southern half of Ireland. The north- 

 east and south-west trend of the line which bounds the territory held 

 by such a species as this seems to indicate clearly that it has spread 

 from south-east to north-west. 



Another large section of the Irish spiders, though wide-ranging, are 

 more restricted in their distribution than the species just considered. 

 These are absent from the Scandinavian peninsula, or only reach its 

 southern districts, while they range across most of central and southern 

 Europe. In Great Britain they do not range far north, while in Ireland 

 they are, as a rule, confined to the south or to the south and west. 

 Typical examples are Atypus piceus, Micrommata virescens, Araneus 

 gihhosus, Lycosa leopardus, Pirata hygrophilus, and most, if not all, of 

 the Attidse. I have elsewhere suggested that the animals of this 

 group have spread in the Irish area from west to east, as well as 

 from south to north, and that they are considerably older than the 

 widespread section which has travelled from east to west ; that indeed 

 they lived in the districts south and west of the area of deposition 



1 "On the Origia of the European Fauna," Proc, R.I. A. (3)vol. iv. No. 3, 1897. 

 See also G. H. Carpenter, "The Problems of the British Fauna," Nat. Science, 

 vol. xi., 1897, pp. 375-386. 



