869 



of tlic cxtcriKil s<'.\u;tl cluiractcu's, ia;iy be expressed iu 

 the following: tiilile of averages: 



The average in tliis relation for the wiiole geiiu.s 



Os)«''/'«.v is 7"7, so that in the first U\u furius tlic 



average falls short of this amount — both of them 



showing' almost the same average — but exeeeds it in 



the last I'urni. in llie first two the [lereentages .sink 

 iinit'ornd\- with increasing age. This is also the case 

 during youth in Osincrus ejierlanus; but after the stor- 

 iiors stage its course of development is reversed — the 

 female characters gain the ascendency in the basin of 

 the Atlantic. Here, as in .several other res])ects, it 

 appears that the course of develojiment was originally 

 common, but has diverged in connexion with a geogra- 

 phical se})aration, which in the Smelts, as well as in 

 the Salmons, i)robablv dates from the Tertiary Period, 

 from the elevation of the liocky Mountains in North 

 America". 



The genus Osmmts was established by Artedi'', 

 who included within its limits, however, the modern 

 Saunis, a Scopeloid genus. 



THE SMELT (sw. .norsen). 



OSMERUS EPERLAXUS'. 



Plate XLl, fi.s:. 1. 



Xiiiiihvr of f/iU-nikcrs on the front of the fr.^f Iu-kiicIiuiI arch 3S—S7', :>S—;2(J of them Jielng sitnutexl on the 



loii-er part of the arch. Height of the anal fn (length of its longest rag) more than s % of the length of the 



hodg or than :U'> % of the length of the head. Length of the middle eaitd^d rags less than, '/j of that of the 



longest an(d rag. 



R. hi: 7(8); D. 



(2)3 



i2)3_. _^ . 



■2— U' ■ 10—11(12)' 



C. ,c + 1 + 17 + 1 + .r; L. lat. (58)62—64(68); L. tr. (supra 

 pinn. ventr.) 13; Vcrl. 60 — 62. 



S\jn. EpeUm de mer et Epelan de riviere, Belox., Nat., Div. Poiss. 

 p. 282 et 284; Kperlanus, Rondel., Pise. Fluv., p. 196; 

 ^ipirinchus et Stinciis, Gesn., Paralip. p. 29; Spirinchtis, 

 ScHONEV., Ichthyol. Slesv. Hols., p. 70; Oamerus rndiis 

 pinn.a> ani eeptendecim, Art., Ichtlnjol., Syn. Pise, p. 21, 

 Descr. Spec. Pise, p. 45; Lin., Fnu Siiec, ed. 1, p. 118. 

 Stdino Eperla7ius, Lin., 6'i/sl. Nat., ed. X, torn. I, p. 310; 

 FiHi Siiec ed. II, p. 124; Bl.. Fisch. Deutschl., part. I, 

 p. 179, tab. XXVIII, tig. 2 (+ var. S. eperlano-nmrinns, 

 11. 182, tab. cit., fig. 1); Retz., Fiia ^uec. Lin., p. 348; 

 L.\CEP. {Osmerus), Hist. Nat. Poiss., vol. V, p. 2.'!1; I'all. 

 {■i'almo), Zoogr. Ross. Asiat., torn. Ill, p. 386; Mrrcu., 

 Trans. Lit., Phil. Soc. N. Y., vol. I, p. 435; Nass. (Osmc- 

 rus), Prodr. Iclithyol. Scand., p. 12; Ekstr., Vet.-Akad. 

 Handl. 1834, p. 7; Yarr., Hist. Brit. Fish., ed. I, vol. II, 

 p. 75; Kr., Danm. Fisk., vol. Ill, pp. 1 et 1215; Clv., 

 Val., Hist. Nat. Poiss., vol. XXI, p. 371, tab. 620; Lloyd, 

 Scandiii. Adventures, vol. I, p. 121; Nilss., SIcand. Fna, 

 Fisk., p. 433; Wideor., Fiskjn, Fisker. Norrb. L., Lai.dlbr. 



Akad. llandl. 1861, p. 9 (scp.); Sieb., .Sitsswasserf. .Mit- 

 leleiir., p. 271; Mgrn, Fint. Fiskfna (disp. Helsingf. 1863), 

 p. 65; Gthr, Vat. Brit. Mus., Fish., vol. VI, p. 166; Fed- 

 DER.-i., Tidskr. Fisk. Kbhvii, IV (1870), p. 100; Coll., Forh. 

 Vid. Selsk. Chrnia 1874, TilUvgsl.. p. 162; Malm, Gbgs, 

 Bch. Fna. p. 549; Seidl., Fna Bait., p. 95; AVinth., Naturh. 

 Tidskr., Kblivii, ser. 3, vol. XII, p. 44; Fedders., ibid., 

 p. 78; Bncke, Fisch., Fischer., Fischs. 0., \V. Preiiss., p. 

 155; Mela. Vert. Fc„n.. p. 344; tab. X; Day, Fish. Gt. 

 Brit. Irel. vol. II, i.. 121, tali. CXXI, fig. 1; MOb.. Hcke. 

 Fisch. Osts., p. 128; Norback, Handl. Fiskev., Fiskafv., p. 

 306; Reut., Su.ndm., Fird. Fisk., tab. XV; Sm. Riksm. Salm., 

 1. c; LiLLJ., So., Norg. Fna, Fisk., p. 630. 



Alheriiia mordax, MrrcH., Trans. Lit., Phil. Soc. N. Y., vol. I, 

 p. 446; Gill. (Osmerus), Smilhson. Misc. Coll., No. 283, 

 p. 32; J.jRD., (iiLi!., Bnll. U. S. Nat. Mus. No. 16, p. 298; 

 Br. Gooue, Fisher., Fish. Iiidustr. U. S., sect. I, p. 543, 

 tab. 199. 



Salmo (Osmerus) spirinchtis, Pall., Zoogr., vol. Ill, p. 387; 

 Cuv., Val., 1. c., p. 387. — nee Lillj., nee Sm. 



Osmerus viridescens, Lesueuh, .Journ. Acad. Nat. Sc. Philad., 

 vol. I, p. 230; Dek., N. Y. Fna, part. IV, Fish., p. 243, 

 tab. 39, fig. 124; Cuv., Val., Hist. Nat. Poiss., vol. XXI, 

 p. 388; Stou.. Mem. Ainer. .-Vcad. Arts, Sc, vol. VI, p. 



" Cf. Smitt, Riksmuseets Salinonider, p. 171, § (5). 



»■ Ichthyol^, Gen. Pise, p. 10. 



' A Latinized form of the French e'perlan, which according to Rondelet refers to the pearly lustre of the coloration. 



