230 [August, 



and perhaps of species — to the piue-feeding fauna and theh- parasites, 

 e.g., Bapalus piiiiarlus L., Ectripis biundidarla Bkh., Trachea piiii- 

 perda Panz., Eiipithecia larlciata Frr., and Opisthograpth llturata CI. 

 among the Lepidoptera ; Carcn.lio abietis L., Bhagimn hifasctatum ¥., 

 Anatis ocellata L., Mysia ohlongognttata L. among the Coleoptera ; 

 sawflies (Lophyrus spp.), and Bhyssa persuasoria among the Hymeno- 

 ptera. This applies, however, only to the more open woods, for in the 

 close plantations where the undergrowth is killed off and the lower 

 branches of the trees are starved and die, there is extremely little 

 insect life of any kind, It is obvious, of course, that where afforesta- 

 tion has taken place, the native fauna will in the end be destroyed 

 unless, as is the case in the open woods, the Original plant life still 

 retains its hold on the soil; in no case in North Yorkshire that I am 

 acquainted with — and I believe this is true of all parts — has there 

 been sufficient planting to destroy any but a comparatively small part 

 of the original flora (this statement does -not apply, of course, to cases 

 where the moor has been reclaimed and converted into pasture, 

 meadow, or arable land) , and hence, though there has been a certain 

 amount of restriction of haunts, in no case has there been total 

 annihilation of the original insect life. 



A much more potent cause of local destruction is the prevalence 

 of moorland fires ; these are occasionally accidental, as was the big 

 fire on Eston Nab two or three years ago, but more commonly they are 

 intentional, their object being to destroy the old coarse heather and to 

 replace it by fresh young shoots which can be eaten by grouse or 

 browsed by sheep. There is here, of Jiecessity, much direct destruc- 

 tion of animal life; but, further, as Mr. F. Elgee of the Middlesbrough 

 Museum has pointed out, on these burnt-out patches or " swiddens " 

 there is frequent change of plant association, bracken usually securing 

 at least the first foothold on the new grou.nd laid bare. This must 

 necessarily cause a local alteration of proportions of animal life, 

 although probably, seeing that the adjacent areas covered with grass, 

 etc., are so vast, it makes little difference to the distribution in the 

 long run. 



As regards destruction of species in the immediate neighbour- 

 hood of Middlesbrough, thei'e is no doubt that the blast furnaces are 

 and will be the chief causes of loss. This is partly a direct result 

 owing to the evil effect of injurious gases, but much more an indirect 

 result owing to dust and smoke, the clouds of which are sometimes 

 so dense that it is impossible to see more than a quarter of a mile 



