CEUSTACEA OF NEW ZEALAND. 273 



increase in size has, I fear, only multiplied its imperfections, and given rise to more 

 questions than have been solved. It has, indeed, shown that no single animal can be 

 profitably studied by itself, but that in attempting to explain one we must study all, 

 and that the one can be thoroughly known only when all are known. 



In concluding his work on the founa of the Swiss Lakes, Forel has pointed out that 

 the phenomena connected therewith, which at first appeared strange, anomalous, and 

 altogether unaccoimtable, were gradually interpreted with increasing knowledge until 

 they harmonized with what we learn of the workings of nature in other places less 

 far removed from man's curioiis gaze. The same statement applies to the consideration 

 of subterranean life, and we can exclaim with Forel — " La nature est grande et belle, 

 paree qu'elle est harmonieuse en tout et partout." 



But one fact that has been impressed upon me more than any other by the very 

 existence of subterranean life is the keenness of the struggle for existence that goes on 

 in the world of animals and plants. I am not aware that he ever did so, but from the 

 tendency of animals to increase in a geometrical ratio, and the consequent struggle for 

 life, Darwin might have deduced the conclusion that every spot on earth capable of 

 supporting life at all would be occupied by its appropriate denizen ; and certainly sucli 

 a conclusion would have been amply verified by the facts now known. Even if we 

 take a single group like the Crustacea, and of these only the smaU and apparently help- 

 less Amphipoda and Isopoda, we find that they have spread until scarcely any place can 

 be named from which they are absent. They are found on land and in the sea ; in 

 running streams and in stagnant ponds ; in hot springs and in frozen pools ; hifh on 

 movmtain-tops and deep in mines ; on the seashore and far out in the ocean ; burrowiu"- 

 in mud and boring into wood and stone ; on the surface of the sea and in its lowest 

 depths ; in the waters on the earth and in the dark recesses of caverns and of the waters 

 imder the earth, where no storm ruffles the everlasting stillness, no light illumines the 

 thick darkness, and no sound breaks the eternal silence. 



XI. Bibliography. 

 I/ist of Works referred to. 



[The originals of many of the works quoted below have been inaccessible to the writer, 

 the contents being, however, knoA\-n to him through abstracts and notices in other works. 

 The chief source from which such information has been gaiiied is given in each case but 

 in many cases the contents of a paper have been knoA^Ti through abstracts in several other 

 works. 



Though the list is far from complete, it is hoped that the chief works bearing on the 

 Subterranean Amphipoda and Isopoda will be found mentioned below.] 



1. AsPER, G. — " Beitriige zur Kenntniss der Tiefsecfauna der Schweizerseeu." Zoologischer Anzeiger 



Band iii. Jalirg. 188n, pp. 130-131, 200-207, 



2. AspER, G.— " Ubcr die Lichtverhiiltuisse iu grossen Wassertiefen." Kosmos, Zeitschrift fiir die 



gesammte Entwicklungslchre, Band i. Stuttgart, 1885. 



Quoted from Wrzesniowski [124, p. 715]. 



