306 Div. 1. VERTEBRATE ANIMALS.— PISCES. Class 4. 



gill-rays; strong spines in the first dorsal, pectorals, and even ventrals; but neither ca3ca nor air-bladder. 

 They form two subgenera : — 



Ilijpostomus, have a small dorsal with one ray ; the labial veiled with papillae, with a small cirrus on each side ; 

 no plates on the belly ; and the intestines spirally convoluted, and as slender as a thread. They inhabit the 

 rivers of South America. 



Loricaria, have one dorsal forwards, the labial veiled with cirri, plates on the under parts of the body, and the 

 intestines moderately large. 



THE FOURTH FAMILY OF THE MALACOPTERYGII ABDOMINALES. 



Salmonid^ (the Salmon, or Trout, Family). 



According to Linnaeus, these formed but one great genus, characterized by a scaly body, all the rays 

 of the first dorsal soft, and the second dorsal adipose, or formed of skin inclosing fat, and without rays. 

 They have numerous coeca, and an air-bladder. Most of tliem ascend rivers ; and their flesh is highly 

 esteemed. They are naturally voracious ; and as the form and armature of their jaws vary greatly, 

 they may be arranged into the following subgenera : — 



Sabno, Salmon and Trout, properly so called. — These have great part of the margin of the upper 

 jaw formed of the maxillaries ; a row of pointed teeth in the niaxillaries, the internuiiillaries, the 

 palatals, and maudibularies, and two rows on the vomer, the tongue, and the pharynx, — being, in fact, 

 the most completely toothed of all fishes In old males, the extremity of the lower jaw is bent up 

 towards the palate, where a groove receives it when the mouth is shut. The ventrals are under the 

 first dorsal, and the anals under the adipose one. They have six gill-rays, or thereabouts ; the stomach 

 is long and naiTow, with numerous coeca ; their air-bladder extends the whole length of the abdomen, 

 and communicates anteriorly with the gullet. Many species are spotted, and their flesh is in general 

 very good. They ascend rivers to spawn, often leaping over cascades of considerable elevation, and 

 finding their way to the brooks and small lakes of the most lofty mountains. [They are understood to 

 return almost invariably to the rivers in which they are produced; and therefore the fixing, at the 

 raouth of a river, of any sort of bar to their progress upwards, is sure to drive them from the estuary. 

 According to Mr. Yarrell, one of the very best authorities, all the family are clouded with transverse 

 dusky patches when very young, — analogous to what occur on all the species of Cats.] 



S. sahir, the Salmon properly so called, is the largest of the genus, with red flesh, and irregular brown spots, 

 which disappear in fresh water ; the cartilagir.ous beak of the male is not much hooked. They inhabit the seas 

 of comparatively cold regions, whence they ascend the rivers for the purpose of spawning, at diflerent times of 

 the year according to the climate,— some in autumn, some in winter, and some in early spring. [The efforts 

 wliicli they make to overcome difficulties in the ascent are very great; and when they have made some progress 

 up the fios.i w.iter, it is equally cruel and impolitic to capture them. It should seem that, in most of the British 

 rivers, Saunon are diminishing in numbers, and becoming inferior in quality, the cause of whicli has not been 

 explained in a satisfactory manner. In Ireland, where tliey have more recently become an article of commerce, 

 they are founil in considerable abundance. Salmon Fry have the tail forked, and the fork disappears as the fish 

 advances in age ; but the margin does not become convex, as in the Uull-trout.] S. humalus, is whitish, spotted 

 witli red and black ; and the snout of the male is narrow, and much crooked in the lower jaw. Its teeth are more 

 robust than those of the true Salmon, and its flesh as red ; but it is inferior in (luality. It is found in the mouths 

 of rivers. S. Scltiefeimullcii, the Sea-trout, is smaller than the former, with the teeth more sli'iuler and longer. 

 Tlie flanks are sprinkled with small crescent-shaped spots, and the flesh is paler than that of the Salmon. S. 

 liitrho [perhaps the Hull-trout, or Gray Trout], grows to almost the size of the Salmon, and has strong teeth, and 

 a pointed lower jaw in the male. 



The lemaiuiiig Trouts are found in all the ciear streams of Europe, especially among mountains ; and they are 

 subject to great variations from age, food, and the nature of the waters ; but these do not appear to account for all 

 the differences. [In the same river. Trout are yellowish brown, with bright crimson spots, where the water is fine 

 and ]mre; and lurid and dark, and greatly inferior in flavour, where it is tinged with peat.] A'. Umamis, Geneva 

 Trout, found in that lake, and some neighbouring ones ; ground colour whitish, with small blackish spots on the 

 I'.ead and back ; sonieliincs forty or fifty pounds in weight: the flesh is white. S.intitc, Salmon Trout, bluish 

 black above, pale on the sides, silvery on the belly, with cross-shaped spots towards the upper part, migratory in 

 clear streams, and esteemed next in value to the Salmon. [It varies a good deal in colour ; and, from its silveiy 

 lustre, it is called White Trout in some parts of IJritain.] ti. fario, the Common, or Kiver Trout, is generally 

 smaller than the last, spotted with brown on the back, and crimson on the flanks,— the crimson spots usually sur- 

 rounded by a pale-coloured circle; common in all the clear streams of temperate countries, and sometimes found 

 two feet and a half long, and fifteen pounds in weight. [The Gillaroo Trout of the Irish lakes appears to be a 

 variety, in which the internal coating of the stomach is modified a little to suit the nature of the food. S.fero.v, 

 the Great Grey Trout, iidi.ibits the deeper lakes, and grows to a large size, but its flesh is inferior.] <S'. savelinus, 



