2. The _Japanese_ district is, like the Mediterranean, distinguished by a great variety of forms; some of them are peculiar to it (marked _J._ in the following list); others occur in the Mediterranean, though also in other districts (_M._) The resemblance to the Mediterranean is even greater than would appear from the following list of genera, inasmuch as a considerable number of species are identical in both districts. Three of the Berycoid genera have hitherto been found in the Japanese and Mediterranean districts only, and nowhere else. Another very singular fact is that some of the most characteristic genera, like _Mullus_, _Zeus_, _Callionymus_, _Centriscus_, inhabit the Mediterranean and Japanese districts, _but have never reached the opposite American coasts, either in the Atlantic or Pacific_; although, at least in the latter, the oceanic currents would rather favour than obstruct their dispersal in the direction towards America. Bold as the hypothesis may appear, we can only account for the singular distribution of these shore fishes by assuming that the Mediterranean and Japanese seas were in direct and open communication with each other within the period of the existence of the present Teleosteous Fauna. Gadoids have disappeared, or are represented by forms inhabiting moderate depths. Neither Myxine nor _Branchiostoma_ are known to have as yet been found. _List of Japanese Shore Fishes._ _Chimæra_ (M.) _Galeus_ (M.), _Mustelus_ (M.), _Triacis_, _Scyllium_ (M.), _Crossorhinus_, _Pristiophorus_, _Cestracion_; _Rhina_ (M.); _Rhinobatus_ (M.), _Narcine_, _Raja_ (M.), _Trygon_ (M.), _Pteroplatea_ (M.) _Percalabrax_ (J.), _Niphon_ (J.), _Centropristis_, _Anthias_ (M.), _Serranus_ (M.), _Apogon_ (M.), _Scombrops_ (J.), _Acropoma_, _Anoplus_ (J.), _Pristipoma_ (M.), _Hapalogenys_ (J.), _Histiopterus_, _Velifer_ (J.), _Dentex_ (M.), _Erythrichthys_--_Mullidæ_ (M.)--_Girella_, _Pagrus_ (M.), _Chrysophrys_ (M.)--_Chilodactylus_--_Sebastes_ (M.), _Scorpæna_ (M.), _Aploactis_, _Trichopleura_, _Pelor_--_Monocentris_ (J.), _Hoplostethus_ (M.), _Beryx_ (M.), _Polymixia_ (M.)--_Platycephalus_, _Hoplichthys_ (J.), _Bembras_ (J.), _Prionotus_, _Lepidotrigla_ (M.), _Trigla_ (M.), _Peristethus_ (M.)--_Uranoscopus_ (M.), _Percis_, _Sillago_, _Latilus_.--_Sciæna_ (M.), _Otolithus_--_Sphyræna_ (M.)--_Lepidopus_ (M.), _Trichiurus_ (M.)--_Zeus_ (M.)--_Caranx_, _Trachurus_ (M.)--_Callionymus_ (M.)--_Lophius_ (M.), _Halieuthæa_ (J.)--_Hoplognathus_--_Cepola_ (M.)--_Centriscus_ (M.), _Fistularia_. _Heliastes_ (M.)--_Labrichthys_, _Duymæria_, _Platyglossus_, _Novacula_ (M.), _Julis_ (M.), _Coris_ (M.) _Sirembo_ (J.)--_Motella_ (M.)--_Ateleopus_ (J.) _Pseudorhombus_, _Pleuronectes_ (M.), _Solea_ (M.), _Synaptura_ (M.) _Saurus_ (M.), _Harpodon_.--_Salanx_ (J.)--_Engraulis_ (M.), _Clupea_ (M.), _Etrumeus_--_Conger_ (M.), _Congromuræna_ (M.), _Murænesox_ (M.), _Oxyconger_, _Myrus_ (M.), _Ophichthys_ (M.), _Muræna_ (M.)