196 SALMONIDiE. 



who also examined this specimen, has identified it with specimens 

 from the Irtish, naming it C sardinella. But as he describes the 

 scales as very small, it is more probable that those Irtish specimens 

 are identical with Coreyonus dujteoides of Xilsson. 



33. Coregonus omul. 



Saliuo aiitumnahs, Pall. Reise, iii. p. 705. 



Omiil, Lepechin, Seise, iii. p. 228, taf. 14. f. 1 (bad). 



Salmo migratorius, Georg. JReise, i. p. 182. 



omul, Pall. Zoop: Poss.-As. iii. p. 406. 



Coregonus omul, Cuv. <§• Val. xxi. p. 528. 



B. 9. D. 13. A. 15. 



Facies Clupeae. Bispithamalem longitudinem raro excedit. Caput 

 parvum, conicum, convexum, rostroque non compressum ; os plane 

 edentulum, maxiUa superiore planiuscule fornicata, lamina mystacea 

 oblonga, majuscula ; inferiore multo longiore. Opercirla branch, 

 rotuudata ; oculi magni. Corpus crassiusculum, pingue, convexo- 

 compressum, dorso quoque nisi prope pinnam, ubi obsoletissime cari- 

 natum. Squamae majusculaj pr^sertim infra lineam lateralem. 

 Color albo-argenteus, supra lineam lateralem demum caerulescens, 

 in summo tan turn dorso fuseidus ; caput etiam, prtcter verticem 

 fuscum, totum albet. Pinna dorsalis ventrahbus dimidio anterior, 

 fiisca, ventrales cum appendice magna, triquctra, lata, fere dimidium 

 pinnae tequante. Cauda bifurca, lacinia superiore majore, fusca. — 

 Maximum quod vidi specimen e mari glaciali long. 22 pollicum, 

 pondere erat 6| librarum, ovis tamen non grave, sed pinguissimum, 

 vuJgo marini pariter et baicalenses ad pondus trium librarum acce- 

 dunt, longitudine tota 1' 4" &", capitis ad operculorum marginem 

 2' Si", a summo maxillae arcu ad oculos 7'", ad finem laminae mys- 

 taceae 10'", ad pinnas pectorales 1" 7|"', inde ad ventrales 4" lOj'", 

 quarum appendices 9'", inde ad pin. ani 3" 7|"', hujus latitiido 1" 6|"', 

 inde ad caudam 1" 3|"'. A summo item oris margine ad pin. dorsi 

 6" 9'", ejus latitude 1" 9'", inde ad adiposam 3" 81'", ejusque lati- 

 tude basi 5'", inde ad initium caudae 1" 4'", long, laciniarum caudae 

 2" 5'". Latitude summa corporis ad pin. dorsi 3" 7'", crassities 2", 

 altitudo capitis ad nucham 1" 11'", crassities 1" 8'". {Pallas.) 



A migratory species, periodically ascending Siberian rivers from 

 the Arctic Ocean. 



34. Coregonus syrok. 



Salmo wimba, Pall. Zoogr. Poss.-As. iii. p. 409 (not L.). 

 Coregonus syrok, Cuv. ^- Val. xxi. p. 499. 



D. 11-14. A. 16-17. 

 Magnitude pedalis. Caput cyprinacenm : os laxius, quam in 

 S. polcur, maxilla inferiore clauso ore subbreviore, eodemve hiante 

 paido longiore. Os et lamina mystaces plane edentula ; hse margine 

 inferiore ad apicem sinuata3. Vertex capitis compress! convexus, 

 aequaliter in rostrum decli^ds. Corpus forma Rutili, squamis majus- 

 culis, mmonbus tamen quam Lavareto. Color argentatus, supra 



