a. Salmones—Salmon and Trout—with teeth on the body of the vomer as well as its head (see Figs. [289] and [290]).
b. Salvelini—Charr—with teeth on the head of the vomer only (see Fig. [291]).
Fig. 292.—Salmo brachypoma.
Of the host of species (the majority of which is unfortunately very insufficiently characterised) we enumerate the following:—[45]
a. Salmones.
1. S. salar (Salmon; Lachs or Salm; Saumon) (Fig. [6], p. 43). The Salmon can generally be readily recognised, but there are instances in which the identification of specimens is doubtful, and in which the following characters (besides others) will be of great assistance. The tail is covered with relatively large scales, there being constantly eleven, or sometimes twelve in a transverse series running from behind the adipose fin forwards to the lateral line, whilst there are from thirteen to fifteen in the different kinds of Sea-trout and River-trout. The number of pyloric appendages (see Fig. [56], p. 131) is great, generally between 60 and 70, more rarely falling to 53 or rising to 77. The body of the vomer is armed with a single series of small teeth, which at an early age are gradually lost from behind towards the front, so that half-grown and old individuals have only a few (1–4) left. The Salmon inhabits temperate Europe southwards to 43° N. lat., and is not found in any of the rivers falling into the Mediterranean. In the New World its southern boundary is 41° N. lat.
2. S. trutta (Sea-trout, Salmon-trout).[46]—Especially numerous in North Britain.
3. S. cambricus (Sewin).—Wales, South of England, Ireland, Norway, and Denmark.
4. S. fario (Common River-trout).