The Zoologist — August, 1869. 1785 



There is an apparent recklessness in the commencement of an 

 exodus, and an uncertainty of result iu carrying it out, that have 

 hitherto baffled all calculation. Certain beings appear where they 

 were previously unknown, and often appear as it seems only to die : 

 they devour our substance, and leave us their dead bodies. The 

 effects are patent. The causes are hermetically sealed in a book we 

 cannot open. Such phenomena have attracted the notice of mankind 

 in all ages ; but, search as we may, we find no explanation that tends 

 to advance our knowledge or satisfy our longing for further inform- 

 ation. The most profound thinkers have done little more than supply 

 us with a formula of words by which to evade explanation. Thus 

 Burke, writing of our own migrations, — the migrations of man, — in- 

 forms us that "These movements of bodies of men are carried out by 

 a sort of migrative instinct." Kingsley alludes to the phenomenon as 

 the result of " restlessness, not nomadic but migratory, arising not 

 from carelessness of land and home, but from a longing to find a home 

 in a new land" ; and, with regard to the Teuton in olden, — aye, even 

 in pre-historic times, — he inquires whether " there is anything won- 

 derful in the belief that the spirit of Woden, 'the mover,' may have 

 moved them and forced them to go ahead as now." Latham, whose 

 reflective power was quite as great as that of the illustrious authors I 

 have mentioned, and whose acquaintance with philology and ethnology 

 is infinitely greater, contents himself with the simple admission that 

 "the southward migration of the Teutons between the days of Tacitus 

 and those of Charlemagne, was of unparalleled magnitude and 

 rapidity." The reader will scarcely fail to observe that these phrases 

 amount to little more than an admission of inability to account for a 

 phenomenon the existence of which admits of no question. 



This " restlessness" is by no means confined to a species, order or 

 class : we trace its existence in the world of Insects, Fishes, Reptiles, 

 Birds, Quadrupeds and Men. A few years only have elapsed since I 

 recorded in the 'Entomologist' the appearance of an aphis-destroying 

 fly on our southern coast: this was Syrphus Pyraslri, an insect of 

 great beauty and considerable size ; examples were sent me in bottles, 

 boxes, and envelopes, and were denominated " horse-stingers," wasps, 

 bees, musquitoes and locusts, and the accounts of the manner of their 

 appearance were equally diverse ; the following facts, however, re- 

 mained after the narratives had been sifted with the utmost care: 

 the swarm came from the land, not from the sea: it was so numerous 

 as to have the appearance of a thick mist for hours continuously : the 



SECOND SRBTES — VOL. IV. 2 Q 



