83-2 



SCANDINAVIAN KISHES. 



But as varieties of Laxoring he adopted 1) from Lin- 

 N^KUS's Fauna Spec. 807, which he calls Laxoring, Lax- 

 orkcl, Fjml-lax, or Eriksmuss-lax, and Spec. 308, which 

 he calls Jioftiiiq, Sikmatk, Tajmeri, or iJidjor, and 2) 

 from Artedi the above-mentioned No. M in Geii. Pise, 

 which he calls Tvdrspol, and No. 12 in Syn. Norn. Fisc. 

 which he calls Laxtinge, Smdiax, or Padrifvare. Gis- 

 ler's third species, Sfndut etc., is indeed ecpiivalent, 

 according to his synonymy, to \o. ."i in Aktedi, (tCH. 

 Pise. : lint all tliat he says of it is that it "has its con- 

 stant haunts in sninll streams, tarns, and lakes, and is 

 quite rare furtlier down the country in the gi'eat cas- 

 cades. Deposits tiie roe in small streams at the middle 

 of Septeml)er. In clear water with a stony or sandy 

 bottom its colour is light, but on a bottom of ooze or 

 nuid ([uite blackish"'. It is not iinproba])le that Gisler 

 meant the Charr, which was of less interest to him and 

 l)erhaps, in consecjuence, less known, for lioth the Swe- 

 dish name of Boding and the Lapp Maud (according 

 to LinnyEus) might easily be confounded with Bofisk. 

 If this be the case, we find in (iIslek the opinion now 

 held l)y most ichthyologists, that within the Scandina- 

 vian fauna there are only three species of the genus 

 Salmo, namely the Lax (Salmon), (hiiig (Trout), and 

 Boding (Charr). 



This o]_)inion was subsequently advanced first by 

 LiLLJEBOEG in (Jfvers. Vet.-Akad. Forhandlingar for the 

 year 1849, where he points out that "the characters 

 which divide Sidmo sahnuhis and Salmo fario have much 

 in conunon with those which distinguish Salmo salar 

 and Sahno erinx. That S. sahnidits is tiie young of 

 the Blanklax (S. S(dar), and S. fario that of the Okia 

 or aS*. eriox, is therefore almost unquestionable, especially 

 as they occur in the same waters, and connecting links 

 between them are known". A more explicit statement 

 of this opinion was Widegken's principal object in 

 his "Bidrag fill kdnnedomen om Sveriges Sahnonider" 

 (Ofrers. Vd.-Akad. Fdrh. 18fi3). 



But another, still more radical reduction uf tiie 

 species had been proposed, conditionally so to s])eak, 

 by NiLSsoN in Of vers. Vet.-Akad. Fdrh. for 1848. 

 "Under such circumstances, and seeing tiiat all the cha- 

 racters prove variable in so liigh a degree, we are 

 almost tempted to ask whether there are here more than 

 two species of Salmons: Trutta and Sahelinus; or the 

 very two which I have designated in my Frodromus as 

 the representatives of distinct groups". Nevertheless he 

 retains tiie Blanklax, Grdlax, Laxdring, and two Charr 



forms as "the most differentiated" or "least intercom- 

 municating" species. In his Skandinavisk Fauna he 

 remarks, however (p. 395), that the (irdlax "is most 

 probably nothing more than an old outgrown form of 

 Salmo Trutta m' Odd' : and we may tlius trace even 

 in Nilsson's writings the opinion "that in the division 

 of tlie true Salmons we have only two species certainly 

 distinct from each other" (Lilej.). While Niessun, how- 

 ever, in his last-mentioned work, di\ided tlie Trouts 

 (Oringarne), including the (iralax. into six (conditio- 

 nally seven) species, Sundevall adopted the above opi- 

 nion, that the true Salmons of Scandinavia belong to 

 one single species. This appears from the titles given 

 by him to the figures in PI. 58 and 59 in the first 

 edition of "Scandinavian Fishes". The male Salmon 

 represented in I'l. 58 is evidently a Blanklax, probably 

 from Norrko|)ing; fig. a in PI. 59 is a Laxdring (Bdr- 

 ting) from tiie Ljusne Elf, and fig. h in the same plate 

 a Grdlax from Lake Wetter; yet all three bear the 

 specific name of S(dar. 



All that different views as to sj)ecific determination 

 has been able to accomplish, has thus been devoted to 

 the elucidation of the Scandinavian Salmon forms. But 

 here as elsewhere the point seems to be, not so much 

 the establishment of a certain number of species, as the 

 explanation of the natural relationship between the 

 forms selected as distinct types. Before these forms 

 can rank as distinct directions of development, it is ot 

 course necessary to show that the characters employed 

 do not coincide with those Avliich mark the common 

 variations of the whole genus undei' the infiuence ot 

 different developmental, sexual, and other circumstances.? 



We begin with the investigation of these circum- 

 stances in the true Salmons, assuming at first the di- 

 stinction between Salmon and Trout, as separate spe- 

 cies, to be true. 



In order to find an expression for those common 

 variations of the Salmons which depend on their growth 

 (their developmental circumstances), we have divided 

 our Scandinavian material, 31(3 specimens, into five 

 groups, arranged accoi'ding to age (the length of the 

 body). These five groups represent different stages of 

 development which are in general well defined both by 

 form and coloration, though the rule is often infringed 

 owing to a cause long known, especially as a result of 

 Widegren's observatiims, namely the fact that the de- 

 velopment is not uniform, one or other of the stages 

 being often persistent in an individual sjiecimen longer 



