While local oscillations, involving changes in coast-lines, have doubtless frequently taken place and are still going on, the past and present distribution of fishes does not alone give adequate data for their investigation. Further, it goes without saying that we have no knowledge of the period of time necessary to work specific changes in a body of species isolated in an alien sea. Nor have we any data as to the effect on a given fish fauna of the infiltration of many species and genera belonging to another. All such forces and results must be matters of inference. The present writer does not wish to deny that great changes have taken place in the outlines of continents in relatively recent times. He would, however, insist that the theory of such changes must be confirmed by geological evidence, and evidence from groups other than fishes, and that likeness in separated fish faunas may not be conclusive. [Illustration: FIG. 184.--Drawing the net on the beach of Hilo, Hawaii. Photograph by Henry W. Henshaw.] FOOTNOTES: [37] _Rheopresbe._ [38] _Bryttosus._ [39] _Leuciscus hakuensis_ Günther. [40] _Leuciscus jouyi._ [41] Formerly, but no longer, called Yeso in Japan. [42] Called Nippon on foreign maps, but not so in Japan, where Nippon means the whole empire. [43] _Pleuronichthys cornutus_, _Hexogrammos otakii_, etc. [44] As _Halichoeres_, _Tetrapturus_, _Callionymus_, _Ariscopus_, etc. [45] Of these, the principal ones are _Oxystomus_, _Myrus_, _Pagrus_, _Sparus_, _Macrorhamphosus_, _Cepola_, _Callionymus_, _Zeus_, _Uranoscopus_, _Lepidotrigla_, _Chelidonichthys_. [46] Among these are _Beryx_, _Helicolenus_, _Lotella_, _Nettastoma_, _Centrolophus_, _Hoplostethus_, _Aulopus_, _Chlorophthalmus_, _Lophotes_. [47] _Beryx_, _Hoplostethus_. [48] _Antigonia_, _Etelis_, _Emmelichthys_. [49] _Lepadogaster_, _Myrus_; _Lophotes_, thus far recorded from Japan, the Mediterranean, and the Cape of Good Hope, is bassalian and of unknown range. _Beryx_, _Trachichthys_, _Hoplostethus_, etc., are virtually cosmopolitan as well as semi-bassalian. [50] In this group we must place _Cepola_, _Callionymus_, _Pagrus_, _Sparus_, _Beryx_, _Zeus_, all of which have a very wide range in Indian waters. [51] _Cryptocentrus_, _Asterropteryx_. The range of neither of these genera of small shore fishes is yet well known. [52] As _Crenilabrus_, _Labrus_, _Symphodus_, _Pagellus_, _Spondyliosoma_, _Sparisoma_. [53] As _Chætodon_, _Lethrinus_, _Monotaxis_, _Glyphisodon_, etc. [54] _Hoplopagrus_, _Xenichthys_, _Xenistius_, _Xenocys_, _Microdesmus_, _Cerdale_, _Cratinus_, _Azevia_, _Microlepidotus_, _Orthostoechus_, _Isaciella_, etc. [55] _Hæmulon_, _Anisotremus_, _Gerres_, _Centropomus_, _Galeichthys_, _Hypoplectrus_, _Mycteroperca_, _Ulæma_, _Stellifer_, _Micropogon_, _Bodianus_, _Microspathodon_.