EXPERIMENTAL ENTOMOLOGY. 29 



The pioneers in these researches were Dorfmeister in Austria, ^Y. H. 

 Edwards of West Virginia, and Professor Weismann of Freilourg. Of 

 late years Professor Max Standfuss, of Zurich, has conducted experi- 

 ments of this kind on a colossal scale, and Dr. E. Fischer, of Zurich, 

 has puhlished some results obtained in a similar way by the application 

 of high and low temperatures to the pupas. Similar experiments of 

 my own are recorded in the Trajisactions and Proceedings of the Knto- 

 iiioloijical Society of London, and it may be taken as now established 

 that not only can the form appropriate to one season be, by the appli- 

 cation of temperatures, usually, but not always, extreme ones, converted 

 into that appropriate to the other season, but that by this process the 

 markings and the colouring of lepidoptera not seasonally dimorphic 

 can be materially changed. Professor Bachmetjew of Sofia has 

 lately published experiments as to the critical temperature point. 

 So far as my present knowledge goes, no such change as pure 

 melanism or pure albinism has thus been induced. M. de Niceville 

 has recorded similar changes produced by exposing pupsB in India to 

 conditions of dryness and moisture. It is much to be desired that these 

 experiments should be tried on many more species, especially on the 

 wonderfully different seasonal forms of species of the African genus 

 Precis, carefully excluding temperature influences. In hybridisation 

 very complete experiments have been made by Professor Standfuss, 

 throwing light on the origination of species. 



Speaking of the subject generally, there is need for observations 

 on a wider range of subjects and on a larger scale than have yet been 

 attempted. The number of observers in entomology is great, as is 

 shown by the voluminous contributions to transactions and magazines, 

 metropolitan and provincial, English and foreign. Many of these 

 contributions are accounts of excursions and their resulting captures, 

 and as such are very interesting to the experienced field naturalist. The 

 mere enumeration of the species captured evokes the recollection of 

 some of the most delightful experiences of one's life — the spring visits 

 to the flowering sallows, the showering down from the trees of quaint 

 and beautiful larvae, the swarms of downy creatures with glowing eyes 

 lightly settled on the sugared tree-trunks, the poise of the shapely 

 hawkmoths over flowers, the return walk on summer nights over the 

 hills studded with gloAvworms, the circling of the sunset light in the 

 sky till it reached the north and its arrival there was signalised by 

 the striking of midnight from the clocks of the distant town, the Avarm 

 nights when we rested on heather waiting for the dawn the approach of 

 which was heralded by the song of the skylarks from their point of 

 vantage far above, the sudden discovery at rest on a leaf of some 

 fairy-like creature of exquisite form and colour never seen before. 

 Recollections so awakened have an indescribable charm, and it may be 

 hoped that the magazines Avill long continue to find place for the 

 chronicle of the "mere collector," and that that much criticised 

 person, if he be one Avho pursues his task in the fields, will continue 

 his delightful work, including the records of it. The devotion to such 

 work seems at least as harmless as that which is dedicated to golf, and 

 often has an utility extending beyond the enjoyment it gives to its 

 devotee. It is of special utility in providing the additional materials 

 so much required by the systematist, who so often laments the imper- 

 fection of his work for want of them. Any one leading structural feature, 



