Clare Island Survey — Apterygota. 32 7 



over northern and central Europe, inhabiting also North America and the 



Arctic regions. 



Isotoma sensibilis (Tullberg). 



The Bills, in Puffins' nests (E. Welch, June, 1910). Also at Islandcara 

 on bark, and Belclare, near "Westport (J. 1ST. Halbert, July, 1911). 



The presence of this delicate insect on such remote outliers as the Bills 

 Bocks is noteworthy. Probably it has a wide range in Ireland. I have 

 seen specimens from Cos. Kerry, Sligo, Wicklow, and Louth ; and it is known 

 to occur both in Scotland and England. It ranges from Novaya Zemlya 

 and northern Europe to Prance, Switzerland, and Austria, and occurs also in 

 North America. 



In recent years, some authors have identified this species with Linne's 

 I. arborea. Linnaniemi states, however (1912, p. 144), that in the latter the 

 two terminal abdominal segments are distinct, while in I. sensibilis they are 

 fused together. 



Isotoma olivacea Tullberg, var. grisescens Schaffer. 



Croaghmore cliffs, 1300 feet (A. W. Stelfox, July, 1911). 



This form has already been recognized in Ireland (Co. Dublin), as well as 



in Scotland and the north of England ; it has a wide range in northern 



and central Europe. The type-form of /. olivacea, from which grisescens 



differs in a few minor structural features as well as in colour (see 



Linnaniemi, 1912, pp. 150-151), is found also in Greenland and the Arctic 



Islands. 



Isotoma viridis Bourlet. 



Apparently common all over the island. Croaghmore summit, dark purple 

 form (July, 1911) ; the Bills Bocks, in Puffins' and Gulls' nests, dark olive- 

 green form (B. Welch, June, 1910); wood near Capnagower, var. riparia 

 Nicolet (B. Welch, June, 1910); Croaghmore cliffs, 1,300 feet, var. pallida 

 Nicolet (A. W. Stelfox, July, 1911) ; under wayside stones near Maum, var. 

 pallida Nicolet (July, 1911). Cn mainland between Boonah and Louisburgh, 

 var. riparia Nicolet (N. H. Foster, May, 1909). 



This is one of the commonest and most widespread of Irish and British 

 insects ; while abroad it ranges over northern and central Europe, Siberia, 

 North America, and Arctic Islands. 



Isotomurus palustris (Muller). 



Croaghmore cliffs, 1,300 feet, a few (A. W. Stelfox, July, 1911); by 

 stream on north slope of Knocknaveen (July, 1911). Also on mainland at 

 Belclare, Westport (J.N. Halbert, July, J 911), and near Lough Moher. 



This, like Isotoma viridis, has a very wide distribution, and extends beyond 



