900 



SCANliINAVlAN FlSHKtS. 



I^ikc tlu! \ (induct' lurnis tlic iiiiiksini h;is hiwj: and dense 

 .^'ill-rnkers; hut tlic jiolciir. like llie t.'^rhir, short and 

 scattered ones. Furtlienuoro the muksun has a compa- 

 ratively shallo\v snout, the pnJcur a comparatively deep 

 snout. The two forms as well as the tvpical Gwyniad 

 live together in the Siberian rivers and the Arctic (_)cean 

 off tlieii' moutlis; and the difference between them coin- 

 cides in an eminent degree with the distinction drawn 

 bv the fishermen in several Swedish lakes between the 

 different kinds of (iwyniad in thcii- catcli. The jiiiiksidi 

 tj'pe they call hMs'ik or //rdiisik (in Norrland asj), when 

 large, or sikloja, when small); while the polcur type 

 l)eai-s the names of .svVr, fctsik, storsik, hritsik or hoften- 

 sik. The ty]>ical iiiihiisik (Houting), \vitli its conically 

 prolongated snout, aJso belongs in fact to the polciiy 

 group. The shajje of the snout has probably been em- 

 ployed time out of mind by the Swedish fishing popu- 

 lation as a character for separate vai-ieties of Gwyniad; 

 but in 1831 L^stadius directed attention to the gill- 

 rakcrs of the asp as a distinction from the slk". That 

 VViDEGREX had also observed the last-mentioned cha- 

 racter, appears from the dra\vings which he left at his 

 death in 1878, and \\hich we liave been enabled here 

 to reproduce (tig. 222, B — F, above, p. 891). 



These t^vo groups of the true Scandinavian G\vyn- 

 iads we distinguished in 18711 liy the names of Core- 

 f/oiiKs Warfnutiiiii and Cur. hiraretiis'' : and they are 

 sometimes well marked even where they occur in the 

 same lake (figs. 224 and 22.5). As an example we njay 

 adduce the Royal Museum collections from Lake Stor 

 (Storsjon) in Jemtland. Scxcn hhisikar and six fefsikar 

 show the followins' constant diffei'ences: 



I NuiiilitT cif jiill-rakcrs on the first bi-anchial .irch of 



1 e.cl.M,le 



! Dqjth of tlu- suout ill »; of the k-iiglh of the head 



,. .. ., ,, reduced. 



,. ,, „ ,, ,, ,. ,. ,. hrcndth of the snout 



I „ „ „ ,. ,, ,. ., ,, length of the maxillaries... 



llA-ngth of the lower ja» in ?i of the length of the head 



„ .. .. redueed 



laxilla 





;m - 1:. 

 «.6— y.s 

 11,4— i;i.2 



riO.o— 62.5 

 27.3—35.7 

 47.1 — 44.0' 

 G2.9 — ay.s<i 



■M -n 



11.1-12.3 

 14.R— 16.7 



66.C— 87.5 

 40.0—46.2 

 40.9 f— 39.3 

 59.3— 51.5 



lilt.i 



-(;i;.7 6S.4.''— 73.0 



But on examining the Fefsik fry of this lake, we 

 find that, even at a length of 70 — 80 mm., only the 

 first tliree characters hold good. Tlius at the outset 

 of their development the two forms stand nearer to 

 eacli other, e^•en after the e.\ternal shape of the body 

 has assumed the character of the group. As is more 

 distinctly shown by our figures, the blasikar of this 

 lake belong to the group characterized in (jUNTHer'' 

 bv "snout vertically truncated," the fefsikin\ on the 

 other hand, belonging to the group'' in which "the 

 snout is obliqueh- truncated, \\ith the nose protruding". 

 The same difference appears, howe^■er, between true 

 blasikar as well, for example in Lake Ring, where, to 

 the best of our knowledge, only blasikar are found'. 

 It is still more difficult to maintain the distinction 

 between the two grou])s where they occur together in 

 the great Swedish lakes or in the sea. The Royal 

 Musciun collection of Gwyniads from Lake \\'etter 

 shows the most varying form of snout-', exemplifying 

 almost all conceivable transition forms between sliallow- 

 snoiited (iwvniads (which we have called tajiiiKirhi/iirln^) 

 — not represented, however, liy fiilh' t\pical speci- 



" "Tlie Asji occurs in all the large lakes, ii|. td Kilpisjiirvi in Tornea L;i|)|jiiiark. Spawns in autumn, in llie rivers in (_)ct(dier. Ii^ 

 exactly like the .Sik, but ilift'ers in the gills, whose spines in the As]) are long and line," L. L. L^estapius, MS in the Royal Museum. 



'' See the Swedish Special e^atulogue at the Fisheries Exhibition in Berlin 1880. Besides the Gwyniads included in this catalogue, my 

 tables of ineasiirements (published in 1886 in Vet.-Akad. Handl.) were accessible in manuscript, and in the course of a public discussion I 

 cited the results of these tables, results which render the specific determination w-i(hin the lavaretus group so untrustworthy that we have 

 rather to deal with local varieties (See GlGHOLi, Annali deH'industria e del coniinercio 1880 (Roma 1881), num. 29, p. 38). 



Subsequently NUssLiN (1882), Klunzinger (1884), and Fatio (1885 — 90) have arrived at the same conclusion, wilh resi.eel te the 

 connexion between the characters derived from the appearance of the gill-rakers and those drawn from the form of the snout, as I niaintained 



the (ddiT oi'iiiioii according tti \\hich 

 roup. 



on the said occasion and published in 1882 in Of vers. Vet.-Akad. Forli. Hut they .■i.lliere 

 species may be determined with certainty, by means of these characters, within the hiriwi'lii 



■■ 43'5 in a single specimen. 



"^ 58'8 in a single specimen. 



'■ 44'4 in a single specimen. 



■' G2'5 in the youngest specimen. 



" Vat. Bvil. Mils., Fisl,., vol. VI, p. 187. 



* 1. c, p. 178. 



' Cf. for example Sjiitt, Jiiksm. iSuhiiuii., tail. \', figg. 78—81, representing four lilii.iitar (Coreg07ius Mls,^oiiii) caught at the same tin: 



->■ See Smitt, I. c, tafl. IV, figg. 69-71 and tafl. V. ligg. 73-7.''), 



'■ From XttuElvug., Ion-, and {iiyyog, snout. 



