126 MAMMALS. 



Perhaps the most interesting circumstance in the distribution of the Seals is the existence 

 of a species in the Caspian Sea, and another in Lake Baikal, notwithstanding that the latter is 

 wholly fresh water, and that the former does not contain one-fourth of the usual saline contents 

 of sea-water. The species in the Caspian (Phoca Caspica) is described as very nearly allied 

 to our common Phoca vitulixa, and that in Lake Baikal as equally close to Phoca fcetida {Ph. 

 anncUafa, Nilss.), a species found in the North Atlantic; and but for their geographical position, 

 no one woidd think of separating them from these species. In fact, the one is the Phoca vitulina, 

 and the other the Phoca rajxiDA. Nilsson and Gray no doubt both consider them distinct, but 

 I do not apprehend that either of them does so from actual observation, and it is scarcely possible 

 to doubt that the peculiarity of the locality must have had some influence on their minds. On the 

 other hand, Pallas, Gmelin, Fischer, and Eadde, regard them as belonging to the two species they 

 resemble, and Radde's personal experience must outweigh any foregone conclusion arrived at by 

 others who have not had the advantage of seeing the animals themselves. 



One's first impression is so much opposed to the possibility of such an occurrence as a 

 marine animal inhabiting permanently a fresh-water lake, that we naturally expect that there 

 must be some mistake about it, and that it may turn out that the animal is an otter, or some 

 unknown species ; but there is no room for doubt about the matter ; it is notorious as a commercial 

 fact, and your ledger is a sore destroyer of j^our theoretical assumjjtions. A regular seal-fishery has 

 for long been carried on in both waters, and in Pallas' time the Baikal seal-fishery was of great 

 importance, and, although much diminished since then, still, so late as 1859, forty individuals 

 were killed at one village ; and, to crown all, Herr Radde brought home with him a specimen from 

 it ; and no specific diflerences can be discovered between it and Phoca annellata. The only 

 difference is that it is of a uniform grey colour, instead of being more or less spotted. This 

 variation, however, is also found in specimens from the North Atlantic. 



Similar instances of other marine animals accommodating themselves to fresh water might be 

 cited. There are species of Dolphins (essentially a marine genus) peculiar to fresh water. There 

 is a species which is confined to the Ganges and another to the Indus, both wholly fresh-water rivers ; 

 another inhabits the Amazons ; and the Delphinapterus leucas ascends the Amour regularly on 

 the breaking up of the ice, and penetrates to a distance of 400 miles up the stream. Mr. Sjjencer 

 St. John mentions a similar fact as occurring with the Shark.* 



Although the Seals are marine animals, they are not so absolutely so, as to render it abstractly 

 improbable that they might acconmiodate themselves to a life in fresh water. The common Seal has 

 been taken in the Firth of Forth above Alloa, where the water is no longer salt, and also far up 

 in the estuary of the Tay. Another Seal, Callocephalus nummularis, which is found in the 

 North Pacific, ascends the mouth of the Amour. Dr. Bennett speaks of a Stenorhynchus leptonyx 

 having been killed in 1859, in the fresh-water of Shoalhaven River in Australia, several miles above 

 the influence of the salt water.f The IIalichcerus gryphus, or Grey Seal, is fomid in the 

 Baltic, as well as in the Northern Seas ; and I have already noted the existence of a pecidiar 



* " It is a curious fact, that far as we are above the frequent these interior waters. ' Not at all,' answei'cd 



influence of the flood-tide, and with so many rapids below the Datu ; ' not more curious than seeing you English 



us, yet sharks arc found here in fresh water. I call it a abandon your own country to come so far and live among 



fact, because native testimony is unanimous. I remember us Jfalays.' " — Spencer St. John, " Life in the Forests ot 



hearing Mr. Crookshank say to the Datu Patinggi, the the Far East." Second Edition, 1863, i. p. 147. 

 principal native chief, that he considered it a very curious t Besnett, George, " Gatherings in Australia," ISGO, 



thing that a fish supposed to live only in the sea should p. 107. 



