NOTES. 253 



I thoroughly agree with the — as I consider — ascertained 

 facts, as to the direct action of food-supply upon fecundity. 

 And that makes it more interesting to me, to await the con- 

 clusions which may be arrived at by Mr. Bunyard, whose very 

 positive statement raises expectation to an unusual extent. 



Regarding the observations upon the fecundity of such 

 species as the Rough-legged Buzzard, Snowy Owl and lemming 

 in Scandinavia ; and the Short-eared Owl and vole in Scotland 

 (and Greece!/) — as ascertained by a "Royal Commission" 

 appointed to examine and report on the " Vole-Plague in 

 Scotland " ; such need not be here enlarged upon. Surely 

 indeed, they, at least, are common property ! 



As regards "some other cause " foreshadowed, or suggested 

 by Dr. Ticehurst — so far, I believe that statement to be quite 

 legitimate and correct. As to what that is, may remain to 

 be " plotted down " and actually " pinned down " yet. So 

 far, I am inclined to the opinion that if " some other cause " 

 be discovered, that cause will be found to be only a cause 

 dependent on the primary cause, or, in absolutely natural 

 sequence of causes and effects. Without going into a long 

 and perhaps needless proof or discussion, the sequence may 

 be something like the following : — 



A. Recurrent abundance of food-supplies affecting fecundity 

 of say — plant-life, seeds, etc., due to exceptional or recurrent 

 climatic changes and conditions. Probably these will be found 

 to recur in cycles of shorter or greater extent and at intervals, 

 let us say — ivithin knowledge — seven to ten years in some 

 cases. 



b. Consequent recurrence of "abnormal" or "cyclic'" 

 fecundity of life dependent on such food-supplies, which have 

 been caused by recurrent cyclic periods of climatic conditions. 



c. Consequent recurrence of other life again dependent on 

 the food-supplies under B. 



d. Consequent recurrent increase of life affected by a, b 

 and c. 



e. Consequent congestion in any area or areas of whatever 

 magnitudes, caused by climatic conditions of cycles of extra 

 recurrent fecundity. 



f. Consequent excess of population so produced in cycles 

 of say seven to ten years as has been demonstrated by large 

 sheaves of vermin schedules returned from most of the large 

 and extensive estates offices in Scotland and elsewhere, and by 

 the "chain of destruction" clearly traced by the Vole- Plague 

 investigations in Scotland (and Greece), and of lemmings 

 by Professor Collett of Christiania and others; and the 



