22 ANNALS OF SCOTTISH NATURAL HISTORY 



has been procured within a short flight of the Solway Firth. 

 Some specimens have been obtained when frequenting arable 

 land, others on the banks of our rivers, and others again upon 

 the sandy flats of the upper reaches of the Firth. But the 

 species is at all times one of our rarest visitors. 



NOTE ON THE OCCURRENCE OF ANABOLIA 

 NERVOSA IN JUNE, WITH REMARKS ON 

 THE EFFECT OF ALTITUDE ON THE TIME 

 OF APPEARANCE OF INSECTS. 



By KENNETH J. MORTON, F.E.S. 



AT the end of June last I spent a few days at Uddingston, 

 on the Clyde, and on the 26th of that month I captured, on 

 the banks of the river, a Trichopteron which at the moment 

 I did not recognise, as it was quite unlike anything usually 

 occurring at that season. On examination, it proved to be 

 a male of the autumnal Anabolia nervosa, perfect in all 

 respects, and apparently just emerged. The other caddis- 

 flies which were out were Lcptocerus nigro-nervosus, 

 L. annulicornis, Allotrichia pallicornis, and other insects of 

 early summer. The causes which led a species so decidedly 

 autumnal to appear so far out of its due time are at 

 present to me quite inexplicable. It is known that insects 

 of autumnal habit, under ordinary circumstances, appear 

 earlier in localities lying at some altitude than they do in 

 lower-lying districts with milder temperature. The present 

 instance cannot, however, be explained under this principle : 

 the date is too early, and the locality practically at sea-level. 

 In connection with this record, it may not be out of 

 place to make a few remarks on the principle just alluded 

 to, as I am not sure that it is one fully appreciated by 

 British Entomologists. The principle appears to be an 

 operative one in Scotland, and it does not seem to be 

 confined to species which are strictly autumnal, but it also 

 exists amongst insects which may be considered as belong- 

 ing rather to summer. Of course due allowance must be 



