282 The h'ish Naturalist, November, 



ON THE INvSECT FAUNA OF SOME IRISH CAVES. 



BY GEO. H. CARPENTER, B.SC. 



Only a few of tlie numerous caves in the limestone districts of Ireland 

 have as yet been searched carefully for a living fauna, but these have 

 already yielded results of considerable interest. The communication 

 dealt with the Springtails(Collembola) that have been discovered in the 

 Mitchelstowu Cave, near Cahir, Co Tipperary, and in the Dunmore 

 Cave, near Kilkenny. 



An exploration of the former cave in 1857, by Haliday and Wright, 

 resulted in the discovery of many specimens of a white blind springtail 

 that was doubtfully identified with the Carniolan cave species, Lipma 

 stilicidii., Schiodte. This insect is now known to be identical with the 

 widespread Z. inermis, TuUberg, a species that inhabits both caves and 

 the upper world in many parts of Europe and North America. All the 

 species of this genus, whether in caves or above ground, are destitute of 

 eyes. 



All the Irish caves seem to be inhabited by Jomoceriis tridentifentSr 

 Tullberg, and in this species pigment and eyes appear to be always well 

 developed. 



Heteromunis viargaritatits, Wankel (^ Tempktonia cavernicola, Carpenter),, 

 a pale blind species, inhabits both Mitchelstowu and Dunmore caves. 

 This form is widespread in the Continental caves, and has not yet been 

 discovered above ground. But it is closeljMallied to H. niiidus (Temple- 

 ton), that occurs in mould. 



Psendosinella cavernaruin (Moniez) abounds in the Mitchelstowu Cave. 

 This is a blind white species that was first discovered in a deep cavern 

 in the South of France. It has since been found in quarry-tunnels and 

 in ants' nests in Scotland, and under stones on fields in Norway. Its 

 congener, P. alba (Packard) — hitherto unrecognised in the British Isles — 

 occurs in Dunmore cave. This species, though white, has well- 

 developed paired pigment- spots on the head, each with two ocelli. It 

 is known to inhabit North America, Norway, and South Germany. 



Smynthnnis ca'cus. Tullberg, is a very interesting blind species from the 

 Mitchelstowu Cave. It has been found also in an old quarry-tunnel near 

 Edinburgh, and in mould in Northern Europe. 



It seems that the only Irish cave-insect that can at all probably be 

 considered blind and degenerate as the result of life in the darkness is 

 Heteromunis margaritatus, which is, perhaps, the modified descendant of 

 H. nitidus. If so, the form must have been independently developed in 

 the different caves it inhabits. 



Such insects as Smynthnrus ccecus and Pseudosinella cavei-narum are 

 evidently very ancient species that have become almost exterminated in 

 the upper world, but are able to hold their ground in the caves. It has 

 lately been suggested by Verhoeff that cave-faunas, as a whole, are 

 survivals rather than special modifications. Certainly the Irish cave- 

 fauna, so far as it has yet been investigated, afford support to this view. 



