The Entomologist's Record and Journal of Variation, 1959, Vol. 71 (Classic Reprint) - Softcover

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Excerpt from The Entomologist's Record and Journal of Variation, 1959<br/><br/>It has also been possible to Obtain a fairly accurate picture of the distribution of certain of the butter?ies in this area during the period roughly covering the second half of the last century. A comparison of the present day butter?y fauna of the region with that of this period shows marked changes to have taken place. Similar and Often syn chronons changes have occurred in many parts of the British Isles during the same period and many of these alterations in distribution and abundance must be attributable to a common cause or causes. The nature of these causes is decidedly obscure but many entomologists (e.g. E. B. Ford, Butter?ies, Chap. 7, and P. B. M. Allan, Moths and Memories, Chap. 3) incline to the opinion that climatic variations are responsible in many cases. If the nature of such in?uences is to be elucidated it appears to the writer that as much local information as possible must be collected and compared. Some of the changes which have occurred have obviously been brought about by man, in cultivation, drainage, and industrialization. This is particularly so in the region dealt with in this article, and it seems that some account of man's in?uence on the butter?y population within this area might be of some future value. Natural divisions or the area The region considered includes a small portion of the Pennine hills and extends eastwards as'far as the River Trent. Reference to the sketch map shows that the area falls into four natural divisions. A. Millstone Grit. This region is largely open heather moorland, the elevation of which varies between about and 900 feet. B. Coal Measures. This division consists of undulating land of a generally lower elevation than that of A. Various types of habitat are included such as rough hill pastures, mixed woodland, and some low-lying land subjected to ?ooding bordering the two main rivers, the Dearne and the Don.

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