METEOROLOGICAL CONDITIONS 97 



order to keep as many as possible in a state fresh enough for 

 preparation. 



All this has been completely changed; not by any means 

 because the birds have actually diminished in numbers ; for when the 

 weather does really once in a way assume moderately favourable 

 conditions, the birds reappear in as large numbers as before. The 

 cause of this change must rather be sought in a complete alteration 

 of the general conditions of temperature and weather which have 

 come about, not suddenly and subject to variations, but gradually 

 and steadily in the course of a long period of time. I am not exag- 

 gerating when I say that the last really warm May we have had 

 here dates back to at least thirty years ago; at present cold and 

 dry north winds prevail at this season ; and had not the expressions 

 Acker-Brogen and Liitj-Finken-Rain been called forth by the 

 memories of those earlier better times, they would surely be no 

 longer existent; for the last twenty or thirty years there has 

 with the exception perhaps of May 1879 hardly ever occurred even 

 a faint approach to these earlier and happier conditions of weather. 



This change in climatic conditions has made itself felt also among 

 other divisions of animal life. Thus, the number of our native 

 nocturnal Lepidoptera has by degrees diminished to such an extent 

 that I have almost completely given up collecting these insects, a 

 diversion which formerly filled up, in a most agreeable manner, the 

 hiatus in the bird-life of our island. Almost all Lepidoptera 

 which fly by night show a marked preference for the beautiful 

 red-flowered umbels of the Red Spur Valerian (Centranthus ruber), 

 which induced me to cultivate a large number of these plants 

 in my garden; but whereas, formerly, every evening each plant 

 used to be the centre of a teeming crowd of all kinds of moths, 

 only scattered individuals now resort to them, with the exception 

 of P. gamma, which still makes its appearance sometimes in com- 

 parative abundance. 



Thus, for instance, for the last ten years I have quite given up 

 hanging out dried apples as a bait in the evenings, because it would 

 be a hopeless task to search for anything upon them. Indeed, the 

 summer evenings are now never warm enough to induce the 

 insects to swarm. As another instance, the large Dung-beetle, 

 Geotrupes stercorarius, which formerly could be obtained here in 

 hundreds, has latterly become quite extinct. I have in vain, within 

 the last few years, offered boys five groschen (equal to about six- 

 pence) for one example of this insect. The large garden spider, 

 Epeira diadema, whose webs used formerly to be stretched in dozens 

 over a thick paling in my garden where, to my annoyance, it used 

 to consume many a much-longed-for moth has quite disappeared 



