ON THE ICHTHYOLOGY OF THE SEAS OF CHINA AND JAPAN. 191 



great zone and project into the colder regions to the southward *. Could 

 we suppose so extensive a belt, having a breadth of sixty degrees of latitude, 

 to be suddenly elevated, we should find the remains of fish scattered over it 

 to be everywhere nearly alike; — the species having a local distribution being 

 comparatively few and unimportant. These spoils of fish would of course, 

 if the opinions of Professor E. Forbes be well-founded, be associated with as- 

 semblages of mollusks and other marine animals, varying according to the 

 depth at which the deposit took place. When we advance northwards in 

 the Atlantic, beyond the 44th parallel, the number of species common to 

 both shores increases. The salmon of America is identical with that which 

 frequents the British Isles and the coasts of Norway and Sweden, and the 

 same is the case with the codfish and several other members of the Gadoid 

 family, and also with some Cottoids. The Cottoids increase in number and 

 variety as we approach the Arctic circle, and this is the case also in the 

 northern arm of the Pacific, though the generic forms differ from those of 

 the Atlantic. From the near approach probably of the Asiatic and Ame- 

 rican coasts at Behring Straits, the fish on both sides are nearly alike, down 

 to the sea of Ochotsk on the one side, and Admiralty inlet on the other. In 

 the sea of Japan, and the neighbouring coasts of China, we find northern 

 forms associated with many common to the temperate and warmer parts of 

 the ocean. In the colder regions of the southern hemisphere there is again 

 a predominance of the Cottoid and Gobioid families, but with a dissimilarity 

 in some of the generic forms, though there are also many genera identical 

 with those of the northern ones. We again find in the southern seas codfish 

 much like those of the north, and Notacanthus and Macrourus, two very re- 

 markable Greenland genera, which inhabit deep water, and are seldom pro- 

 cured except when thrown up by storms, have recently been discovered 

 on the coasts of New Zealand and South Australia. Several genera are 

 peculiar to the southern hemisphere, such as Notothenia, Bovichthjs and 

 Harpagifev, and of these we find the same species at the Falkland*, Cape 

 Horn, Auckland Islands and Kerguelen's Land ; in fact, in the whole circle 

 of the high latitudes. The fish of the New Zealand seas differ little from 

 those of Van Diemen's Land and South Australia. 



From what has been stated, it appears that the ichthyology of the Austra- 

 lian seas has an Asiatic character f as opposed to the Atlantic or South 

 American assemblages of species. The fish of the Pacific coasts of America 



* Neither the objects nor the limits of this report admit of a full consideration of the 

 manner in which an archipelago extending in longitude favours the diffusion of many spe- 

 cies of fish ; but I may remark cursorily, that the multiplication of places of deposit for 

 spawn on the shores of the islands and intervening coral banks, and the appropriate food 

 that many fish find in such places, may have much influence. The Chat odont idee, Labridce, 

 Balistida; and other groups of littoral fish, are among the most remarkable for the extensive 

 range of species. , Some of the LophohrancM who inhabit floating beds of sea-weed, to which 

 they adhere by their prehensile tails, have also an extensive range; the moveable and exten- 

 sive beds of Sagasso being, in fact, as far as they are concerned, so many islands. 



f Mr. Gray informs us, that setting aside the Marsupials of Australia, which arc of a dif- 

 ferent group from the South American ones, the ordinary quadrupeds, of which many species 

 are now known, have an Asiatic character; and that all the Australian reptiles are like those 

 of the Old World, while those which inhabit the Galapagos belong to American groups. The 

 genera, he goes on to remark, of the Australian reptiles are mostly peculiar, but belong to 

 Asiatic, or at least to Old World families. One species, named Gecko perns, is common to 

 Australia and to India and its islands, and the Plestiodon b-lineatum, which is very common 

 in North America, exists also in Australia and Japan, and may perhaps have been introduced. 

 The genus, which is a very natural one, and well-characterized, consists of five species, viz. 

 the cosmopolite one that we have mentioned, a second one inhabiting America, a third one 

 belonging to North Africa, and two to China. Specimens from different localities have been 

 carefully examined by Mr. Gray, who considers the diffusion of the species of this genus 

 as an anomaly in the geographical dietribution of reptiles. 



