Cakpenter — A List of the Spiders of Ireland. 209 



of the Pleistocene Drift. " Prosthesima Latreillei and Oxyptila praticola 

 seem members of this section which have been able in Ireland to 

 spread farther east and north than the others. 



A comparatively small, but well-marked section of the Irish 

 spider fauna is to be assigned to the northern group. These species 

 are abundant in the north of Europe, but seem to die out towards the 

 south, while some of them re-appear in I^orth America, suggesting 

 the range of such mammals as the Varying Hare, As examples may 

 be given Prosthesima subterranea, Crijplioeca sylvicola, Textrix denticu- 

 lata, Ammirohitis fenestralis, Erigone longipalpis^ Tmeticus Suthivaitii, 

 Pathifphantes nigrinus, Lepldhyphantes terricola, Linypliia insignis, 

 Bolyphantes luteolus, Pardosa palustris, and P. herhigrada. It is 

 interesting to notice that several of these species — Ammirolius fenes- 

 tralis, for example — are abundant over the whole of Ireland, while 

 they are absent or very scarce in southern England, notwithstanding 

 that they range far south in France. It is impossible to suggest what 

 can have prevented the southern advance of these species in Great 

 Britain, when we see that they have passed so far on in Ireland and 

 on the Continent, But the fact clearly indicates that they entered 

 our area from the north. 



A yet smaller group of Irish spiders can be assigned with confi- 

 dence to the oldest section of our fauna — the Lusitanian or south- 

 western section, characteristic of south-western Europe and the 

 Mediterranean shores, sometimes with a restricted distribution in 

 Ireland, sometimes extending into western or northern Britain — 

 Bysdera crocota, Agroeca celans, A. gracilipes, Tegenaria liihernica, 

 Iheridion aulictim, Lascsola inornata, Teutana grossa, Cnephalocotes 

 curtus, and PorrJiommu myops are examples of these. 



There remain certain species which are decidedly western in 

 their range, and are therefore to be reckoned among the old 

 members of our fauna, though there is not sufficient evidence to 

 warrant us in assigning them definitely to the south-western group ; 

 some of them at least may have come into our area from the north. 

 These species, some of which are among the commonest of Irish 

 spiders, are absent from the Austro -Hungarian fauna or only present 

 in the western regions of that country, while a few have not been 

 recognized at all on the Continent. Examples are — Oonops pidcher, 

 Agroeca proxima, Oxyptila Jlexa, Hahnia montana, Amaiirohius similis, 

 Theonoe minutissima, Neriene ruhens, Erigone promiscua, Tmeticus 

 prudens, Batliyphantes pidlatus, Leplitliypliantes Blachivallii, and 

 Pardosa nigriceps. These western species seem able to hold their 

 ground in numbers in our island, and specially in Ireland, while 



K.I. A. PEOC, SER. Ill,, VOL. V. P 



