Page:Encyclopædia Britannica, Ninth Edition, v. 12.djvu/696

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678 ICHTHYOLOGY [DISTRIBUTION. species ; Mullidse, 35 ; Sparida?, 130 ; Squamipinnes, 130 ; Cir- rhitid^e, 40 ; Heterolepidina, 12 ; Scorpseniase, 120 ; Cottidse (part), 100 ; Cataphracti (part), 20 ; Trachinidfe, 100 ; Scisenidae, 100 ; Sphyrrenidae, 15 ; Trichiuridae, 17 ; Elacate, 1 ; Nomeidse (part), . > ; Cyttidte, 8 ; Stromateus, 9 ; Mene, 1 ; Carangidae (part), 130 ; Kurtiilae, 7 ;, Gobioilon, 7 ; Callionymina, 30 ; Discoboli, 11 ; Batrachidse, ?4 ; Pedieulati (part), 11; Blenniidae, 90; Acantho- clinidae, 1 ; Teuthididae, 30 ; Acronuridre, 60 ; Hoplognathidae, 3 ; Malacanthidae, 3 ; Plesiopina, 4 ; Trichonotidae, 2 ; Cepolidae, 7 ; Gobiesocidae, 21 ; Psychrolutidae, 2 ; Centriscidae, 7 ; Fistulariidae, 4. ACANTHOPTKUYUII PnARYNGOGNATHi. Pomacentridae, 150 species ; Labridae, 400 ; Embiotocidae, 17. AXACANTHINI. Gadopsidee, 1 species ; Lycodidae, 15 ; Gadidse (part), 50 ; Ophidiidae (part), 40 ; Pleuronectidae., 160. PHYSOSTOMI. Saurina (part), 16 species ; Salmonidae (part), 7 ; Clupeidae (part), 130 ; Chirocentridae, 1; Chilobranchus, 1 ; Muraen- idae (part), 200 ; Pegasidae, 4. LOPHOBRANCHIT, 120 species. PLECTOGNATHI, 178 species. CYCLOSTOMATA. Myxinidic, 5 species. LEPTOCARDII, 2 species. Total number, 3587 species. These types of shore fishes are distributed over the fol lowing oceanic areas : 1. The Arctic Ocean. II. The Northern Temperate Zone. A. The Temperate North Atlantic. 1. Tbe British district. 2. The Mediterranean district. 3. The North American district. B. The Temperate North Pacific. 1. The Kamtchatknn district. 2. The Japanese district. 3. The California!! district. III. The Equatorial Zone. A. The Tropical Atlantic. B. The Tropical Indo-Pacific. C The Pacific coast of Tropical America. 1. The Central American district. 2. The Galapagos district. 3. The Peruvian district. IV The Southern Temperate Zone. 1. The Cape of Go d Hope distri-t. 2. The South Australian district. 3. The Chilian district. 4. The Patagonian district. V. The Antarctic Ocean. As with freshwater fishes, the main divisions of the shore-fish faunae are determined by their distance from the equator, the equatorial zone of the freshwater series corre sponding entirely to that of the shore-fish series. But as marine fishes extend farther towards the poles than fresh water fishes, and as the polar types are more specialized, a distinct arctic and antarctic fauna may be separated from the faunae of the temperate zones. The two subdivisions of the northern temperate zone in the freshwater series are quite analogous to the corresponding divisions in the coast s ries. Tn the southern hemisphere the shore fishes of the extremity <.< f Africa form a separate district of the temper ate zuiie, whilst the freshwater fishes of South Africa were found to be tropical types. The marine series of the southern temperate zone is also much more diversified than the freshwater series, and admits of further subdivision, which, although in some degree indicated in the freshwater series, does not entirely correspond to that proposed for the latter. ^ ARCTIC OCEAN. The shore fishes clearly prove a con tinuity of the arctic circumpolar fauna, as the southern limit of which we may indicate the southern extremity of Greenland and the Aleutian Archipelago, or 60 N. lat. Towards the north, fishes become less in variety of species and fewer in number of individuals, and only very few genera are restricted to this fauna. The highest latitude at which shore fishes have been observed is 83 N. The late Arctic Expedition collected at and near that latitude specimens of Coitus quadricornis, Icelus hamatus, Cydopterus spinosus, Liparis fabridi, Gym- nelis viridis, and Gadus fabridi. The number would probably have been larger were it not that the difficulties of collecting fishes in these high latitudes are almost in superable for the greater part of the year. So far as we know, the fishes north and south of Behring s Straits belong to the same generic or family typea as those of the corresponding latitudes of the eastern hemi sphere, though the majority are specifically distinct. But the information we possess of the fishes of the northern most extremity of the Pacific is extremely scanty and vague. Farther south, whence now and then a collection reaches Europe, we meet with some European species, as the herring, holibut, and hake. Chondropterygians are very rare. Of Acanthoptery- gians the families of Cottidce, Cataphracti, Discoboli, and Blenniidce are well represented, and several of the genera are characteristic of the arctic fauna. Characteristic also is the development of Gadoid fishes, of which some thirteen species, belonging to Gadus, Merluccius, and Molva, form one of the principal articles of food for the inhabitants of the coasts of the Arctic Ocean. The Blen- noid Anacanthini or Lycodidce are limited to the Arctic and Antarctic coasts. Ammodytes and a few flat-fishes (Hippoglossoides and Pleuronectet;) are common in the more temperate parts. Labroids only exceptionally penetrate so far towards the north. Physostomes are very rare, and are represented only by a few species of Clupea and by Mallotus. The arctic climate is still less favourable to the existence of Lophobranchs, only a few of Synyna- thus and Nerophis being present in the more southern latitudes, to which they have been carried by oceanic currents from their more congenial home in the south. Scleroderms and Plectognaths are entirely absent. The Gadoids are accompanied by Myxine, which thrives in them as a parasite. NORTHERN TEMPERATE ZONE. Temperate North At lantic. This part of the fauna may be subdivided into three districts : 1. The fishes of the north-eastern shores, viz., of the British Islands, of Scandinavia so far as it is not included in the arctic fauna, and of the continent of Europe south- wards to about 40 N. lat. : British district. 2. The fishes of the Mediterranean shores and of the adjoining shores of the Atlantic, including the Azores, Madeira, and the Canary Islands : Mediterranean district. 3. The fishes of the western shores, from 60 to about 30 N. lat. : North American district. 1. The British district shows scarcely any marked distinctive features ; the character of its fauna, is simply intermediate between that of the Arctic Ocean and the Mediterranean district ; truly arctic forms disappear, while such as are also found in the Mediter- 1 ranean make their appearance. With regard to the abundance of

individuals and variety of fishes also, this district forms a transition

I from the north towards the south. Besides the few arctic Chondropterygians, all of which extend into this district, the small shore dog-fishes are well represented 1 (Mustclus, Galeus, Scyllium, Pristiurvs); the ubiquitous Jlhina or 1 monk-fish is common ; of rays, Raid, predominates in a variety of species over Torpedo and Trygon, which are still rare. Of Acanthopterygians, Ccnl.ridcrmicUhys, Icelus, Triglops, and Aspidophoroides do not extend from the north into this district ; and Coitus, Anarrhichas, Centrouotus, Stichcevs, and the Discoboli disappear within its limits. Nearly all the remainder are genera which are also found in the Mediterranean district. The following are the principal forms known to propagate on these shores : Labrax ; Serranus, Polyprion, Dcntcx ; Mullus ; Cantharus, Pagrvs, Pagcllus; Scbastcs; Cottits, Trigla, Agonus; Trachinus ; Sciocna (?), Zeus ; Trachurus, Capros ; Callionymus ; Discoboli ; Lophius ; Anarrhichns, Ccntronotus, Stichceus ; Blenniopt, Zoarccs (not in I the Mediterranean) ; Ccpola ; Lepadogaster. Of the Anacanthini the Gadoids are as numerous as in the Arctic Ocean, most being common to both districts ; but, whilst the majority show their northern origin by not extending into the Mediterranean, Ammodytes and most Plcuroneciidcc prove themselves to be the more southern representatives of this order. In the

British district we find Hippoglossus, Hippoglossoides, Rhombus,