288 FISHES. 



3. The coast-line of the Chilian district extends over 20 

 degrees of latitude only, and is nearly straight. In its nor- 

 thern and warmer parts it is of a very uniform character, 

 and exposed to high and irregular tides, and to remarkable 

 and sudden changes of the levels of land and water, which 

 must seriously interfere with fishes living and propagating 

 near the shore. No river of considerable size interrupts 

 the monotony of the physical conditions, to offer an addi- 

 tional element in favour of the development of littoral 

 animals. In the southern parts, where the coast is lined 

 with archipelagoes, the climate is too severe for the majority 

 of fishes. All these conditions combine to render this district 

 comparatively poor as regards variety of Shore fishes, as will 

 be seen from the following list : — 



*Callorhynchus ; Scyllium, Acanthias, Spinax ; Urolo- 

 phus. 



Serranus, Plectropoma, Polyprion, Pristipoma, Erythrich- 

 thys ; *IIaplodactylus ; *Scorpis ; Chilodactylus, **Mendo- 

 soma ; Sebastes, * Agriopus ; Trigla, Agonus ; *Aphritis, 

 *Eleginus, Pinguipes, Latilus, ISTotothenia (1 sp.) Umbrina ; 

 Thyrsites; Trachurus,Caranx,*SerioleILa; Porichthys; **Myx- 

 odes, Chnus ; Sicyases, Gobiesox. 



Heliastes ; **Malacopterus ; *Labrichthys. 



Merluccius ; *Genypterus ; Pseudorhombus. 



Engraulis, Clupea ; Ophichthys, Murajna. 



Syngnathus. — *BdeUostoma. 



Of these genera six only are not found in other districts 

 of this zone. Three are peculiar to the Chilian district; 

 Porichthys and Agonus have penetrated so far southwards 

 from the Peruvian and Californian districts ; and Polyprion 

 is one of those extraordinary instances in which a very speci- 

 alised form occurs at almost opposite points of the globe, 

 without having left a trace of its previous existence in, or of 

 its passage through, the intermediate space. 



