10 THE CAUSES WHICH PROPAGATE 



Blanc Nez, lulled by the sleepy^ hazy dirl of the large Leaf 

 Crickets, amid a rare profusion of bluets and poppies. Scour- 

 ing in my search for insects the skirts of that vasty quiescent 

 plain, the projected prolongation of the Deal flats stretching 

 out northward from the Calais bluffs away to the pine-clad 

 Baltic, I soon began to recognise the relict of that secret 

 habitat which in olden time replenished our south-eastern fauna, 

 and conferred on it its charming alluvial trait. Once a dreary 

 but faunistically rich fenland, where baronial castles lay girt 

 about with whispering reeds and clamorous marsh fowl, the 

 forgotten home, as I doubt not, of our large Copper Butterflies, 

 where Swallow Tails still fly — this low-lying district may be now 

 known by a black peaty deposit, shelving beneath the Channel 

 waves and running into reefs ; but shoreward, arid and covered 

 with sand drift, incessantly pounded from transported chalk 

 flints and sea shells by the tides tumbling their breakers along 

 the shore. 



Here, around sluice and ditch, still struggles on a remnant of 

 a once rich coleopterous fauna of lacustrine aspect, ill at ease 

 amid the changed and changing surroundings. Many of these 

 species of beetle are common to Calais and our own Fen district, 

 others are rare or never found on this side of the Channel. Of 

 the latter, when strolling along the sand dunes, I have myself 

 picked np two, perhaps the largest and most conspicuous, 

 Carabus curiaceus and the Jardinier (Auratus) ; and at Sand- 

 gate, the small Chafer, Rhizotrogas rufescens, Lt., widely dis- 

 tributed on the Continent, becomes quite common in summer ; 

 and yet this is a species as far as I can learn that has nerer 

 reached, or at least never propagated on, British soil. Nearer 

 Lille occurs the Purple-edged Copper, seldom or never seen in 

 this country ; and this butterfly, with the Queen of Spain 

 Fritillary, and a Blue- winged Locust, confers a thoroughly 

 Gallic asjDect on the spot. The local moths of our south- 

 eastern shores also might be all with a little trouble hunted up 

 by an enterprising collector in their colonies and fastnesses 

 around Calais and Boulogne. '^ 



Now it so hai^pened, among other things, in the year 



* For infoiination concerning the Highland Insect Fauna, see " Fauna 

 Perthensis," by Dr. F. Buchanan White, and Review, by R. C. E. Jordan, M.D., 



