A OOMPARISON OF ANTIPODAL FAUNAS. 



r.v Theodore Gill. 



(Kind Niiviiiilior, 18«7.) 



PREFATORY. 



A comparison of antipodal faunas, it was thought, might reveal the salient characteristics of 

 such, in(lci)eii(leut of climatic considerations, and none were better fitted for the purpose of study 

 than the piscine inhabitants of the British islands on the one hand and the New Zealand waters on 

 th(^ other. Hoth jiioujjs of islands agree ai)pr()xiinately in size and the temperature of the waters. 

 The difference in tiie distances from neigiiboring lands introduces, it is true, another factor, but, 

 far from being the cause of embarassnient, it might tend to throw light on the subject. For these 

 reasons a comparison was instituted between the regions in question. 



The British fishes have been quite recently fully described and illustrated, and our knowledge 

 of the subject, so far at least as specific diversities are concerned, has been nearly brought up to 

 date by Surgeon Francis Day in his "Fishes of Great Britain and Ireland." A summary of the 

 families and including orders, as understood by the present writer, has also been given iiua com- 

 parison of the faunas of the British islands and Massachusetts iu the Eeport of the Smithsonian 

 Institution for 1883. 



The Xew Zealand fishes, at time of presentation of this memoir, had not been collected in any 

 nomenclator (the last published list of the sjjecies having appeared in 1872), and the abundant 

 literature on the subject, whereby the number of species had been nearly doubled, was scattered 

 through many volumes. It was necessary, therefore, to bring togetlufr and consult tlie numerous 

 articles in which the information was embodied. Since then a very useful and ably compiled 

 "List of the Xew Zealand Fishes" has been issued by Prof. J. W. Ilutton, long and favorably 

 known for his researches on the fishes as well as many other animals of the colony. A number of 

 the changes made in the original memoir have thereby been anticipated and others have been 

 meanwhile forestalled by European naturalists.* Nevertheless, there is still much to be done in 

 clearing up doubts respecting many siiecies, ami numerous changes have been mad(> in the memoir, 

 as now published, which appear to be justified by evidence now at hand. A point will be gained 

 if renewed attention is directed to questions here r.aised, and science will be the beneficiary, 

 whether the conclusions now enunciated are verified or falsified. 



"Among the rectilicatious wliicli would have been the (irsf to appear in the memoir, if it had been published soon 

 after tbedate of prnsintation, were new ({Ciiuric names for those since ealled Plagiogenion, Xeplolichthnn, and Jiicherocfroa, 

 the elimination of Clenolnbrus knori from the Labrinw and its association, in common with J'inutepteruK rfreicii and 

 Oirella pcrvoidtH, with (lirella timplcx, and the rcctific.ition of the synonymy of the rr:ino.sco]>ids and Leptosoopids, 

 on the basis established by Prof Iliitton. The anticipation is, however, compensated for by finding that 1 had inde- 

 pendently reached the same comlimionN as that excellent naturalist. 



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