27 2 Proceedings of the Royal Irish Academy. 



respect the district shares a characteristic of the rest of Ireland, there 

 being only twenty -three kinds recorded from this country. 



Among the rarer dragonflies are Sympetrv.m scoticum, which occurs both on 

 Clare Island and on the adjacent mainland. The local Bracliytron pratense 

 occurred on the wooded hillside at Belclare, and Mr. King had previously 

 taken it near the convent at "Westport. A much rarer -species is the little 

 Ischnura pumilio, which Mr. King found many years ago on the Carrowbeg 

 Paver. One hot day in July I also met with a specimen flying over marshy 

 _groundby a small lough (Doo Lough) quite close to Louisburgh. According to 

 Mr. Lucas it is a very local British insect, occurring in the south-eastern 

 parts of England. Both of the handsome dragonflies Calopteryx virgo and 

 C. splendent occur on the wooded banks of streams in the neighbourhood of 

 Westport, the former species being an addition to the local list. 



The most interesting insect discovered during the Survey is a caddisfly, 

 limnophilv.s fiisrinervis, which it was my good fortune to capture while 

 collecting on the wooded shores of Lough Lannough, close to Castlebar. This 

 insect proved to be unrecorded from the British Isles. 1 The first specimen, a 

 male, was taken on June 17th. 1909, and on a subsequent visit in July a few 

 females were found in the same place, so that it is probably not uncommon 

 there. It is remarkable that so conspicuous an insect should have been over- 

 looked in these countries, and it is extremely likely that it awaits discovery on 

 some lake-shore in northern Britain. Lough Lannough also yielded a 

 Mayfly. Leptophlebia vespertina, which was not previously known to occur 

 in this country. 



This district is decidedly poor in stoneflies (Perlidae) ; none of the larger 

 species, Perla, Dictyopteryx, &c, were found, although there are many st reams 

 affording a suitable habitat for these insects. 



Apart from those species which are known to be common and widely 

 distributed throughout Europe, there is a decided preponderance of northern 

 over southern species. Amongst forms which may perhaps be included in the 

 latter category are the dragonfly Ischnura pumilio, the mayfly Cloeon simile, 

 and the caddisfly Polycentropus Kingi. 



There can be little doubt that most of the twenty-four species taken on 

 Clare Island found their way to that area in former times while it was still 

 joined to the mainland "With few exceptions the Neuroptera are winged, yet 

 the comparatively weak and fitful flight of the majority of these insects would 

 seem to preclude the possibility of their having flown across the three miles of 

 ocean which, at its narrowest part, separates the island from the mainland. 



1 The known Continental range of this caddisfly is northern Lapland, Finland, Sweden, 

 Lithuania, Germany, Sarepta, Denmark ; and a variety (var. itb.Utu McLareh) has been found in 

 Persia. 



