Encyclopaedia Britannica > Volume 21, ROT-Siam

SALMONIDiE
all of them being considered by Day as a variety, S. albus, of Sahno
trutta.
(7) S. gallivcnsis, Giintlier. An anadromous species from Galway,
distinguished by the acutely pointed but not elongate snout, broad
convex head, small eye, feeble teeth, feeble maxillary and mandible,
and by extremely thin and short pyloric appendages, which are not
longer than one inch nor thicker than a pigeon’s quill. According
to Day a variety of S. fario.
(8) S.ferox, Jard. and Selby {Edinb. New Philos. Journal, 1835,
xviii.). A non-migratory species inhabiting the large lochs of the
north of Scotland and several lakes of the north of England,
Wales, and Ireland. Pneoperculum crescent-shaped, the hinder
and lower margins passing into each other without forming an
angle. According to Day a variety of S. fario.
(9) S. orcadensis, Gunther, from Loch Stennis in Orkney.
(10) S. stomachicus, Gunther (the Gillaroo). From lakes of
Ireland. Thick stomach. Feeds on shells {Limnsous, Ancylus).
(11) S. nigripinnis, Gunther. Non-migratory species inhabiting
mountain pools of Wales, also Lough Melvin, Ireland.
Day mentions also the following varieties of S. fario:—
S. cornubiensis, Walk, Artedi;
Swaledale trout, from Swaledale, Yorkshire ; and
Crassapuill trout, from Loch Crassapuill, Sutherlandshire.
Many species of Sahno exist which are confined to limited areas
in the continent of Europe. An account of these is given in the
Brit. Mus. Catalogue, which also contains references to the litera¬
ture. One of these, S. macrostigma, Dumeril, is a non-migratory
form occurring in Algeria, and is the southernmost species of the
Old World. Three non-migratory species exist in the rivers
belonging to the basin of the Adriatic. In the Alpine lakes of
central Europe five species are known, which resemble in habits
the forms found in British lakes, ascending the streams which
feed the lakes, in order to spawn. Two of these species inhabit
the Lake of Constance, one the Lake of Geneva. Fario argentcus,
Cuv. and Yah, found in the Atlantic rivers of France, is con¬
sidered by Dr Gunther a distinct species, by Mr Day as a synonym
of S. trutta. One migratory species is known from the Eidfjord
river in Norway ; two land-locked species from Lake Wener in
Sweden.
The species of Salmo belonging to the Pacific Coast of North
America have been described by Eichards in Faun. Bor. Amer.,
by Suckley in Nat. Hist. Washington Territory, and by Girard in
Proc. Acad. Nat. Sc. Philad. Only one species need be mentioned
here, and that on account of the importance it has acquired in
connexion with the work of the United States Fish Commission :—
Salmo irideus, Gibbons {Proc. Cal. Ac. Nat. Sc., 1855, p. 36);
Solar iridea, Girard {Proc. Acad. Nat. Sc. Philad., 1856, p. 220
and U. S. Pac. JR. JR. Explor.—Fish, p. 321, pi. 73, f. 5, and pi. 74)
(the Californian, Mountain, or Eainbow Trout). B. 10 ; D. 14 ;
A. 14 ; L. lat. 140. Caudal deeply emarginate. Body and dorsal
and caudal fins with numerous small black spots. A non-migratory
species in rivers of Upper California.
For the same reason as in the preceding case, the following
species of the eastern slope of the North American continent is
introduced:—
Salmo namaycush, Penn {Arct. Zool., ii. p. 139), Cuv. and Yah
(xxi. p. 348) (Lake Trout). B. 11-12 ; D. 13-14 ; A. 12 ; V. 9 ; L.
lat. 220. Prajoperculum very short, without lower limb ; head
very large. Teeth strong ; those on the vomer persistent through¬
out life, and in single series. Inhabits all the great lakes of the
northern part of North America.
B. Subgenus Salvelinus :—
Sahno alpinus, L. (the Charr, Yarrell, Brit. Fishes, 3d ed.).
D. 13 ; A. 12 ; P. 13 ; Y. 10 ; L. lat. 195-200 ; Yert. 59-62 ;
Caec. pyh 36-42. Body slightly compressed and elongate. Length
of head equal to height of body in mature specimens and two-
ninths or one-fifth of total length ; maxillary extends but little
beyond the orbit in the fully adult fish. Eye one-half, or less
than one-half, of the width of the interorbital space. Teeth of
moderate size. Inhabits lakes of Scandinavia, Scotland (Helier
Lake, Hoy Island, Orkneys; Sutherlandshire'; Loch Koy, Inver¬
ness-shire), and probably Iceland.
S. hillinensis, Gunther {Proc. Zool. Soc., 1865, p. 699). D. 14-
15 ; A. 13 ; P. 13 ; Y. 9; L. lat. 180 ; Yert. 62 ; Csec. pyl. 44-
52. Head, upper parts, and fins brownish black ; lower parts
Avith an orange-coloured tinge in the male; sides Avith very
small, light, inconspicuous spots. Anterior margins of the loAver
fins Avhite or light-orange-coloured. Loch Killin, Inverness-shire.
Considered by Mr Day as a variety of S. alpinus.
S. willughbii, Gunther {Proc. Zool. Soc., 1862, p. 46, pi. 5) ;
Charr, Willughby {Hist. Pise., p. 196), Penn {Brit. Zool.), and
Yarrell {Brit. Fish., 3d ed.) (the Charr of Windermere). D. 12-
13 ; A. 12 ; P. 13-14 ; Y. 9-10 ; L. lat. 165 ; Yert. 59-62 ; Cajc.
pyl. 32-44. Sides Avith red dots ; belly red ; pectoral, ventral,
and anal Avith Avhite margins. Lake of Windermere ; Loch Bruiach
(Scotland). Considered by Mr Day as a variety of S. alpinus.
S. perisii, Gunther {Ann. and Mag. Nat. Hist., 1865, p. 75);
223
Torgoch, Willughby {Hist. Pise.) and Penn {Brit. Zool.) (the
Torgoch or Red Charr). D. 13 : A. 12 ; P. 12 ; Y. 9 ; L. lat. 170 ;
Vert. 61 ; Caec. pyl. 36. Sides Avith numerous red dots ; belly red
in the mature fish; pectoral, ventral, and anal Avith white
margins. Lakes of North Wales (Llanberris). Considered by Mr
Day as a variety of S. alpinus.
S. grayi, Gunther {Proc. Zool. Soc., 1862, p. 51). D. 13 ; A. 12 ;
P. 13-14; V. 9 ; L. lat. 125 ; Yert. 60; Caec. pyl. 37. Sides
Avith scattered light-orange-coloured dots ; belly uniform silvery
whitish, or Avith a light-red shade ; fins blackish. Lough Melvin,
Ireland. Considered by Mr Day as a variety of S. alpinus.
S. colii, Gunther {Proc. Zool. Soc., 1863) (Cole’s Charr, Couch,
Fish. Brit. Isles). D. 14; A. 12; P. 13 ; V. 9 ; L. lat. 160;
Vert. 63 ; Caec. pyl. 42. Bluish black above ; sides silvery Avith
scattered light-salmon-coloured dots; belly reddish ; fins black,
the anal and the paired fins Avith a reddish tinge, the anal and
yentrals Avith a narroAv whitish margin. A small species 7 to 8
inches long from Loughs Eske and Dan, Ireland. Considered by
Mr Day as a variety of S. alpinus.
The above are all the British species.
S. umbla, L. {Syst. Nat.), Cuv. and Yal. D. 12 ; A. 12-13 ; P.
14 ; Y. 9 ; L. lat. 200 ; Yert. 65 ; Csec. pyl. 36. Commonly called
in French Ombre Chevalier. LoAver parts AAdiitish or but slightly
tinged with red. Lakes of Constance, Neuchatel, and Geneva.
Considered by Mr Day as identical Avith S. alpinus. Other species
have been described from lakes in Europe and Asia, but are imper¬
fectly knoAvn ; for an account of them see Gunther’s Catalogue.
The folloAving American species of Charr is one of those cultivated
by the American Fish Commission :—
S. {Salvelinus) fontinalis, Mitch. {Trans. Lit. and Phil. Soc.,
Ncav York, i. p. 435), Cuv. and Val. (xxi. p. 266) (Brook Trout).
B. 12; D. 12; A. 10; L. lat. 200; Csec. pyl. 34. No median series
of teeth along the hyoid bone. Prajoperculum short in longitudinal
direction, with the lower limb very indistinct. Rivers and lakes of
British North America, and of the northern parts of the United
States. Introduced in Britain.
2. Of the genus Osmerus only three species are described in the
Brit. Mus. Cat., one of which is British :—
Osmerus eperlanus, Lacep., Linn, (the Smelt; Fr., fjperlan;
Scotch, Sparling or Spirting). B. 8 ; D. 11 ; A. 13-16 ; P. 11 ; V.
8 ; L. lat. 60-62 ; L. transverse xrT ; Csec. pyl. 2-6 ; Vert. 60-62.
Height of body much less than length of the head, which is a quarter
or tAvo-ninths of the total length to base of caudal fin. Snout pro¬
duced. Vomerine teeth and anterior lingual teeth large, fang-like ;
posterior mandibular teeth larger than the anterior ones, Avhich form
a double series, the inner series containing stronger teeth than the
outer one. Back transparent, greenish ; sides silvery. Adult size
10 or 12 inches. Coasts and numerous fresh Avaters of northern and
central Europe.
Osmerus viridcscens, Lesueur, another species scarcely distinct
from O. eperlanus, but with scales a little smaller, occurring on the
Atlantic side of the United States.
Osmerus thaleichthys, Ayres, occurs abundantly in the Bay of San
Francisco.
3. Of Coregonus forty-one species are described in the Brit.
Mus. Cat. Four species are found in Britain :—
C. oxyrhynchus, Kroyer, Linn., Cuv. and Yal. (xxi.). Called the
Houting in Holland. B. 9 ; D. 14 ; A. 14-15 ; L. lat. 75-81 ; L.
transverse ^1®.; Vert. 58. Snout produced, with the upper jaAV
protruding beyond the loAver, and in adult specimens produced
into a fleshy cone. Length of the lower limb of operculum 1J to
1| times that of the upper. Pectoral as long as the head Avithout
snout. Found on coasts and in estuaries of Holland, Germany,
Denmark, and Sweden. Captured recently (three specimens
only) in Lincolnshire, near Chichester, and at the mouth of the
Medway.
C. clupcoides, Lacepede ; C. pennantii, Cuv. and Yal. (the Gwy-
niad of Lake Bala, Schelly of UllsAvater, PoAvan of Loch Lomond;
sometimes called the Freshwater Herring). B. 9; D. 14-15; A. 13-
16; L. lat. 73-90 ; L. transverse T®r; Csec. pyl. 120; Vert. 38/20.
Snout Avith upper jaAV not produced. Pectoral larger than the head.
Fins black or nearly so. Lakes of Great Britain.
C. vandesius, Richards {Faun. Bor. Amer.)-, C. albula, Cuv. and
Yal. (the Vendace). D. 11 ; A. 13 ; Y. 11 ; L. lat. 68-71 ; L.
transverse X3X; Vert. 56. Castle Loch, Lochmaben in Dumfries¬
shire.
C. pollan, Thompson {Proc. Zool. Soc., 1835), Cuv. and Yal. (the
Pollan). D. 13-14; A. 12-13; V. 12 ; L. lat. 80-86; L. transverse
X9X; Vert. 60-61. Tavo jaws of same length. Teeth if present
very minute. Bluish along the back, silvery along the sides and
beneath. Usual length of adults 10 to 11 inches, maximum 13
inches. Ireland, in Loughs Neagh, Erne, Derg, Corrib, and the
Shannon.
Thirty-seven species of Coregonus have been distinguished
besides these four. Some are migratory ; but the greater number
are inhabitants of large lakes. The anadromous species are confined
to the Arctic Sea, and the greater number belong to the coast and