6 4 



SCIENCE-GOSSIP. 



left other regions of Western Europe where they 

 were common at the period when they inhabited 

 Britain. The one cause above all others for the 

 disappearance of birds from any particular region 

 is the difficulty of obtaining regular supplies of 

 natural food. It is not necessary that the supply 

 of this food should have actually ceased in any 

 district, if the animals which depend upon it are 

 unable to adapt themselves, while feeding, to 

 artificial disturbances which may grow up around 

 them. In fact, if we take the list of those birds 

 that formerly habitually bred in this country, but 

 no longer do so, we shall find that they are all 

 more or less afflicted with timidity or shyness of 

 man and his works, or that their food-supply is gone. 

 Otherwise they are birds which have had to suc- 

 cumb to the competition of others more numerous 

 or more assertive than their own species. As an 

 instance of this, it appears to be only a question of 

 time before house-sparrows will drive away one 

 of our most lovely and interesting summer migrants 

 — the house-martins. These pugnacious little 

 finches have latterly contracted the ■ habit of 

 driving away the martins from their nests, which 

 the sparrows themselves then occupy. 



Taking the other point of view, namely, the 

 consideration of those birds which now regularly 

 breed in these islands, we find, first, they are 

 species that have adapted themselves to man's 

 civilization, or inhabit localities which have not 

 been affected by railways, factories, cultivation of 

 the land, or game preservation. With regard to 

 the first type, or such as have contented themselves 

 with the association with mankind, we need have 

 no fear of their extermination. Their habits will 

 in the future tend to a greater familiarity with 

 human civilization and consequent increase in 

 numbers. This point of view is confirmed by the 

 fact that some of the formerly shiest of all shy 

 birds, the wood-pigeons, have within quite recent 

 times come to breed in our largest and most noisy 

 cities throughout western Europe, herding with 

 sparrows and starlings. 



Other birds which are so frequently quoted by 

 the humanitarian school of nature-lovers, would 

 never, under existing circumstances, become per- 

 manent breeders in this country. Neither is it 

 probable, under its wildest conditions, were they 

 ever more than casual breeders. Among these are 

 the often-quoted hoopoes and golden orioles. Most 

 animals, indeed, we may say all species, live within 

 certain well-defined geographical limits, and Great 

 Britain cannot be within the limits of the above 

 two kinds, nor of some other birds which so rarely 

 fall into the hands of the " selfish collectors." 

 They may bs safely looked upon as storm-blown 

 individuals, or unwilling migrants from some other 

 cause, who would in course of time either return 

 to their more congenial haunts or be killed by 



cruel nature on the first approach of winter, 

 or by other means. Were they birds which could 

 readily adapt their habits to our country they 

 would in time past have bred in such numbers 

 that their offspring, under the influence of the 

 hereditary passion for returning to the place of 

 their birth to reproduce their species, would come 

 as regularly every season as do the nightingales 

 or the cuckoos. 



In every division of nature and in every region 

 of the earth there appear to be waves in the 

 abundance and scarcity of certain species of the 

 feral inhabitants. Returning to those of Britain, 

 we may consider one of the most studied 

 and best understood of the great orders — that of 

 the Lepidoptera, or butterflies and moths. In my 

 own time of active observation, extending to nearly 

 forty years, we have known some species in many 

 parts of the country which were generally common, 

 or at least by no means rare, to have practically 

 disappeared. As an example I may mention the 

 " brown-tail moth " (Porthesia (Liparis) chrysorrhoca), 

 which twenty years since was a comparatively 

 common species throughout the south of England, 

 but is now rarely or hardly ever found. The 

 same applies to that handsome butterfly, the 

 " black-veined white" (Aporia cratacgia), which was 

 abundant half a century ago throughout southern 

 England and South Wales. Without mentioning 

 others, these two instances are sufficient to prove 

 that some other agency than that of the collector 

 must have caused their disappearance ; because, 

 in the first place, there have never been in this 

 country a sufficient number of persons who re- 

 quired specimens of these once common species to 

 have exterminated them. Neither have some of 

 the localities where they both abounded ever been 

 visited by entomologist or collector. 



I have every sympathy with those who have 

 founded societies for the protection of our wild 

 birds, and brought about Acts of Parliament for 

 their preservation. As I have said earlier in these 

 lines, I look with abhorrence on theuseless, senseless 

 and vulgar destruction of any kind of wild life. I 

 admire equally the efforts which certain collectors 

 of butterflies and moths have been making for the 

 formation of an association to protect disappearing 

 species in our fauna. Doubtless their efforts 

 may prolong for a few years the stay of these 

 species with us ; but if their diminution is due to 

 the forces of nature or to their inadaptability to 

 accommodate themselves to human civilization, no 

 amount of dilettante preservation will stop their 

 ultimate extinction. While forming these societies 

 and advocating the abstention from collecting, 

 humanitarians must be careful not to allow senti- 

 mental feelings to interfere with the proper 

 acquisition of representatives of our fauna for 

 scientific purposes. I venture, however, to hold 



