. British and Irish Salmonidæ. hleven trout, which is likewise a rapid grower,loses them rather sooner than the burn or loch form, while to say that in themature they are invariaWy in a single row is erroneous. At the same time it isnot here advanced that rapidity of growth is the sole cause of this, but thedcciduonsness of the teeth appears to be owing to the absorption or narrowing ofthe tooth-bearing ridge on the vomer, in consequence of which, first from being inpairs, they become in a single row and finally fall out. {See fig. 45, page 197 ante.) In the following seven specimens of Lochle
. British and Irish Salmonidæ. hleven trout, which is likewise a rapid grower,loses them rather sooner than the burn or loch form, while to say that in themature they are invariaWy in a single row is erroneous. At the same time it isnot here advanced that rapidity of growth is the sole cause of this, but thedcciduonsness of the teeth appears to be owing to the absorption or narrowing ofthe tooth-bearing ridge on the vomer, in consequence of which, first from being inpairs, they become in a single row and finally fall out. {See fig. 45, page 197 ante.) In the following seven specimens of Lochleven trout the condition of thevomerine dental system was as follows :—In a female 20 inches long, 2 teethexist on the hind edge of the head of the vomer, and 3 along the front half of itsbody, the two first of which are almost opposite one another. (2) In a viaJe9 inches long, 2 teeth at hind edge of vomer, 2 at the front end of the body, and 7in an irregular zigzag line, almost in one continuous row, while their points turn. Fig. TiO. Outlines, lite size, of tail fins o£ Lochleven trout reared in ijonds atHowietoun. 1, at 2 months old: 2 and 3, at 13 months : 4, male, 113 months: 5, 6, 7,males, at 30 months. From specimens in the British Museum collection : 8, female,12 in. long: 0, female, 13 in. long: 10. female, 1:^-8 in. long: 11, female, ISl in. long:12, male, 17 in. long. From Howietoun fish : 13, female, 7 years old, 227 in- long: 14,male, 7 years old, 22 in. long. FRESH-WATER TROUT—LOCHLEVENS DESCRIBED, 223 alternately to the right and left. (3) In a, female 10-9 inches long, 2 at hind edgeof head of bone, 2 in a line at the commencement of the body, and 8 as in thelast specimen, Imt more distinctly in pairs. (4) In a female 135 inches lono-, 2at hind edge of head of vomer, then 4 in a single row, next a pair taming one toeither side, and lastly, 4 more single ones. (5) In a male 14 inches long, 2 teethat hind edge of body of vomer, 9 in a single row along the bo
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Keywords: ., bookcentury1800, bookdecade1880, bookidbritishirish, bookyear1887
