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A WAVE OF LIFE.* 

 By W. H. Hudson, C.M.Z.S. 



For many years, while living in my own home on the 

 Pampas, I kept a journal, in which all my daily observations on 

 the habits of animals and kindred matters were carefully noted. 

 Turning back to 1872-3, I find my jottings for that season 

 contain a history of one of those waves of life — for I can think of 

 no better name for the phenomenon in question — tbat are of 

 such frequent occurrence in thinly-settled regions, though in 

 countries like England, seen very rarely, and on a very limited 

 scale. An exceptionally bounteous season, the accidental miti- 

 gation of a check, or other favourable circumstance, often causes 

 an increase so sudden and inordinate of small prolific species, 

 that when we actually witness it we are no longer surprised at 

 the notion prevalent amongst the common people — that mice, 

 frogs, crickets, &c, are occasionally rained down from the clouds. 



In the summer of 1872-3 we had plenty of sunshine, with 

 frequent showers ; so that the hot months brought no dearth of 

 wild flowers, as in most years. The abundance of flowers 

 resulted in a wonderful increase of Humble Bees. I have never 

 known them so plentiful before ; in and about the plantation 

 adjoining my house I found, during the season, no fewer than 

 seventeen nests. 



Tbe season was also favourable for mice ; that is, of course, 

 favourable for the time being, unfavourable in the long run, 

 since the short-lived, undue preponderance of a species is 

 invariably followed by a long period of undue depression. These 

 prolific little creatures were soon so abundant that the dogs 

 subsisted almost exclusively on them ; the fowls also, from 

 incessantly pursuing and killing them, became quite rapacious 

 in their manner ; whilst the Sulphur Tyrant-birds and the Guira 

 Cuckoos preyed on nothing but mice. 



The domestic cats, as they invariably do in such plentiful 

 seasons, absented themselves from the house, assuming all the 

 habits of their wild congeners, and slinking from the sight of 

 man — even of a former fireside companion — with a shy secrecy 



* From ' The Field ' of Feb. 3, 1883. Communicated by tbe author. 



