FISHES. 151 



The graylino; and the trout often inhabit the same waters, but not altogether in 

 harmony. It is said tliat the grayling devours the eggs of the trout. It is certain that 

 the trout feed on the young grayling. As a food-fish the grayling, of course, ranks high ; 

 but the true sjjortsman will hardly seek such fish as these to fill his frying-pan. They are 

 considered gamey fishes, altliough less strong than the brook-trout, and perhaps less 

 wary. The five or six known species of grayling are very closely related, and are 

 doubtless comparatively recent offshoots from a common stock, which has now spread 

 itself widely through the northern regions. 



The common grayling of Europe { Thi/mallus thi/mallus), found throughout north- 

 ern Europe, and as far southward in the mountahis as Hungary and northern Italy. 

 The name Thymallus was given by the ancients, because the fish, when fresh, had the 

 odor of water thyme, an odor which the duller sense of the moderns now fails to 

 detect. Other sjiecies are described from Russia and Siberia. 



The American grayling {Thijinallus sic/infer), is widely distributed in British 

 America and Alaska. In several streams in northern Michigan and in Montana occurs 

 another form, known to anglers as the Michigan grayling {Thymallus onturiensis). 

 This variety or species has a longer head, smaller scales, and the dorsal fin rather 

 lower than in the northern form {siffni/er), but the constancy of these characters in 

 specimens from intermediate localities is yet to be tested. It is probable that the 

 grajling once had a wider range to the southward than now, and that so far as the 

 waters of the United States are concerned, it is tending towards extinction. This 

 tendency is of course being accelerated in Michigan by lumbermen and anglers. 



The genus Oncorhynchus contains those species of Salmonidfe which have the 

 greatest size and value. They are in fact, as well as in name, the king salmon. The 

 genus is closely related to Salmo, with which it agrees in general as to the structure of 

 its vomer, and from which it disagrees in the increased number of anal rays, branchi- 

 ostegals, pyloric coeca and gill-rakers. The chai-acter most convenient for distinguish- 

 ing Oncorhynchus, young or old, from all the species of Salmo, is the number of devel- 

 oped rays in the anal fin. These, in Oncorhynchus are thirteen to twenty, in Salmo 

 nine or ten. 



The species of Oncorhynchus have long been known as anadromous salmon, con- 

 fined to the North Pacific. The species were first made known one hundred and 

 thirty years ago, by that most exact of early observers, Steller, w-ho described and dis- 

 tinguished them with perfect accui-acy, and gave them, as vernacular names, the 

 Russian names which now stand in scientific nomenclature for the different sjiecies. 



Since Steller's time, writers of all degrees of incompetence, and writers with scanty 

 material, or with no material at all, have done their worst to confuse our knowledge 

 of these salmon, until it became evident that no exact knowledge of any of the 

 species remained. In the current system of a few years ago, the males of the five 

 species known to Steller constituted a separate genus of many species, while the 

 females were placed in the genus Salmo, and the young formed still other species of a 

 third genus, called Fario. Not one of the writers on these fishes of twenty-five years 

 ago knew a single species definitely, at sight, or used knowingly in tlieir doscrijitions 

 a single character by which species are really distinguished. Not less than thirty-five 

 nominal species of Oncorhynchus have already been described from the North Pacific, 

 although, so far as is now known, only the five originally noticed by Steller really 

 exist. The descriptive literature of the Pacific salmon is among the very worst 

 extant in science. This is not, however, altogether the fault of the authors, but it is 



