DISTRIBUTION OF SHOEE PISHES. 293 



Shore Fishes, — The fishes of the first category number upwards 

 of three thousand five hundred species. Their range in the north 

 extends to, or beyond, the eighty-third parallel of latitude, but in 

 the Southern Hemisphere no species have been found to pass be- 

 yond the sixtieth parallel, although, doubtless, they exist along 

 some of the more southerly shore-lines. The Arctic fauna, or the 

 fauna occurring north of the sixtieth parallel of latitude, is, as far 

 as we are warranted in believing, a strictly homogeneous one, iden- 

 tical types largely characterising both the Old and the New World 

 divisions. The more extensively represented families are, among 

 the spiny-rayed fishes, the bull-heads (Cottidse — Cottus, Icelus, Tri- 

 glops), the Agonidse, lump-suckers (Discoboli), and blennies (Blen- 

 niidse— Anarrichas, wolf -fish) ; and among the anacanths the cod- 

 fishes, with the cod (Gadus), hake (Merlucius), and ling (Molva). 

 Among the physostomous fishes, or those in which the air-bladder 

 is provided with a pneumatic duct, the herring (Clupea) is repre- 

 sented by a limited number of species. The cartilaginous fishes 

 are very scarce ; indeed, thus far only one species, the Greenland 

 shark (Lsemargus), is known to penetrate north of the Arctic cir- 

 cle. The chimsera, spiny dog-fish (Acanthias), and ray, are met 

 with along the southern borders of this tract. 



The Antarctic shore fauna is in many respects closely related to 

 the Arctic, although nearly one-third of the generic types are 

 peculiar. As in the north, the cartilaginous fishes are scarce, 

 being represented by a single species of shark (Acanthias), and one 

 or more species of ray (Raja, Psammobatis). The Scorpaenidae and 

 Agonidse among bony-fishes have each one genus, Sebastes and 

 Agonus respectively, which is held in common with the Arctic 

 fauna. The lophobranchs have in addition to the northern pipe- 

 fish (Syngnathus) the remarkable Protocampus, represented by a 

 single species of the Falkland Islands (P. hymenolomus). A most 

 interesting fact connected with the Antarctic fauna is the recur- 

 rence of types belonging to the far north, which are wanting in 

 the intermediate region. This we see in the single species of 

 spiny dog-fish (Acanthias vulgaris), which is a member of the 

 Arctic and north temperate faunas, but is absent from the equa- 

 torial region. The hakes comprise two species, one of which is 

 restricted to the northern waters and the other to the southern; 

 and a similar separation is found among the species of the Arctic 



