78 The Irish Nahiralht. [March, 



observable on the lepidopterous fauna of that county. Yet I 

 found on the east slope of Mangerton, where the recorded 

 annual rainfall often considerably exceeds 60 in. as against 

 about 46 in Co. Cork and 41 in Co. SHgo, that the normal 

 typical coloration prevailed, and likewise at Killarney ; while 

 darkly clouded forms seem to be strictly localised on the coast, 

 which militates strongly against the theory in respect of this 

 unstable species. If we accept the view I have put forward as 

 to the selective agencies at work in producing these melanic 

 forms, the inquiry suggests itself whether in similar localities 

 the same influences have affected other species in like manner. 

 Owing to the dangers and difficulties which beset the 

 collector in such rugged and inaccessible spots I have not very 

 much evidence to produce. But remarkable examples are 

 not w^anting. We should remember however that the 

 Geometridae from their habit of resting with outspread wings 

 on rock faces are likely to be more pliable than Noctuse in 

 assuming protective coloration, and of these I have been 

 unable to secure any examples on the islands on the south- 

 west coast, except a few Melaiiippe fluctitata from Durse3% 

 dark forms, but not numerous enough to be accepte 1 as 

 evidence. Probably very few immigrants would be able to 

 survive the selective ordeal. Dursey Island is easily accessible, 

 but being separated from the mainland by only a narrow 

 sound, and being some three miles in length, and having 

 a large proportion of grass and herbage in comparison 

 to cliff and rock, does not afford a field in which the selective 

 agencies referred to exercise a very severe test. If it were 

 possible to explore carefully the fauna of such places as Sher- 

 kin Island off Baltimore, The Cow, The Bull, the two Hogs off 

 Kenmare Bay, The Skelligs, Pufiin Island, Inishna-bro, 

 Inishtearaght, Inishvickillaune, etc., the result would, I am 

 sure, prove of the utmost scientific interest. I append a few 

 results of my attempts in this direction on three of them. 

 Agrotis hicernea is extremely black. Hadena oleracea, darker 

 than u.sual, with the stigma reduced in size and dark yellow, 

 and the white subterminal line attenuated. Dianthcp.cia cccsia, 

 very dark, but D. nana (one specimen only taken) tj'pical. 

 DianthcEcia capsophila, however, shows remarkable melanism 

 in the three examples captured, The ground-colour is very 



