. sft fluke (sectioned) Q L left fluke '^ (sectioned) Fig. 7. Diagrams of the caudal peduncle, a, viewed from the left side {Balaenoptera viusculus, from True, 1904). b, viewed from behind and from the right side, as in Plate XXXIII, fig. 6 {B. physalus). When whales dive at unusually steep angles they submerge the fin before the peduncle and the streamline form of the latter in transverse section is then seen to best advantage. By its great depth— 4 ft. in a 65 ft. whale (Howell, 1930, p. 204)—the flukes are kept well beneath the surface as long as possible. In considering the eflFects of the
. sft fluke (sectioned) Q L left fluke '^ (sectioned) Fig. 7. Diagrams of the caudal peduncle, a, viewed from the left side {Balaenoptera viusculus, from True, 1904). b, viewed from behind and from the right side, as in Plate XXXIII, fig. 6 {B. physalus). When whales dive at unusually steep angles they submerge the fin before the peduncle and the streamline form of the latter in transverse section is then seen to best advantage. By its great depth— 4 ft. in a 65 ft. whale (Howell, 1930, p. 204)—the flukes are kept well beneath the surface as long as possible. In considering the eflFects of the flattened head and its mobility, the streamlined dorsal fin and the caudal peduncle, it would be interesting to know more about the habits of other whales. The Right whale is also a plankton feeder and visits the surface to breathe but is said to be slow in its movements. In this whale the maxillae are laterally narrow and dorsoventrally curved; mobility of the head is reduced by extensive fusion of the cervical vertebrae and it has no dorsal fin. Killer whales and dol- phins which feed upon active prey have very much larger dorsal fins placed farther forward. The
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Keywords: ., bookcentury1900, booksubjectocean, booksubjectscientificexpediti
