OCR Text |
Show 4 SEXUAL SELECTION. PAil'l' If. " tho intermaxillary bones of the npper ja'~·" n (Figs. 2G cl 2,.., ) In our salmon this chango of strncturo an t. . 1 S l hlsts only during the breeding-season; but 111 t l8 a rn.__o lycaodon of N.vV. America tho change, as 1\Ir. J. h. F l:;. 26. llea<l of mu!e of conm:o:t slllmon (Saluw salar) during !he brccLiing-3enson. [This drawing, ns well ns nll.thc others in lh~ presen t .chapter, bav~ hCPI~.cxccn.ted. by the well-known ar tist, 1\lr.li. l•urd. un<ler the k111d snpcnntendencc ot Or. Gnnthct , hom ~pccimc ns In tltc llritb h .l\1.uscnm.J. G Ynrrcll, 'History of Dritish Fishes,' vol. ii. 1830, p. 10. C IIAP. XII. FISHES. 5 Lord 7 believes, is permanent and best marked in the older males which have previously ascended the rivers. In these old males the jaws become developed into immense hook-like projections, and the teeth grow into Fig. 27. Head of female salmon. re~ular fangs, often more than half an inch in length. \VIth the European salmon, according to 1\fr. Lloycl,s ~ : ~he ~ntui:ali st in Vancourcr's I sland,' vol. i. 186:1, p. 51. · Scnmhnav1nn Adv:mturcs,' vol. i. 185l, p. 100, 10l. |