| OCR Text |
Show 1886.] MR. R. COLLETT ON BAL^NOPTERA BOREALIS. 255 in colour. They form on the inner edges of the baleen-plates a dense, rather curly covering, which appears to indicate that the food of this species consists of only very small animals. VIIL Blowholes and Fu?*rows. The Blowholes lie in two long furrows somewhat converging anteriorly ; their distance from the end of the snout, in a specimen having a total length of 43 feet, was somewhat over 6| feet (2100 millim.). The length of the furrows was from 3/0 to 410 millim., between these ran a shorter central furrow. The Farrows.-These run, as in the other species, along the whole length of the lower jaw, from the symphysis to the angle of the mouth, and extend to the middle of the belly. The upper 8 to 10 are short and terminate in the axilla, and are about 2 feet in length. The others, about 20 in number (from 15 to 34) on each side, are long and extend backwards to the centre of the belly about one foot beyond the end of the flippers. One or more short furrows wedge themselves in between the long ones. The total number of long furrows is thus from 30 to 44, to which must be added the 8-10 shorter upper ones ; altogether 38 to 58. In addition, the eye is surrounded by two very short horizontal furrows, and in some examples there were also found (as in No. 4) traces of from 20 to 30 short, oblique furrows anteriorto the dorsal fin. The furrows permit the body to expand to nearly double its normal girth. IX. Hairy Covering. This consisted in an adult female of 11 hairs on each side of the lower jaw, each about 10 millim. long, and two other hairs on each side, situated somewhat behind these; altogether 26 hairs. In the foetus the covering of hair was more plentiful. On the smallest of the foetuses described further on (No. 1), the total length of which was 14^ metres, the hairs were visible, but quite short. In foetus No. 3, the total length of which was not quite 2\ metres, they were arranged on the lower jaw in three rows, comprising 3 hairs in the upper and lower rows respectively and 11 in the central row ; altogether on each side 17 hairs. On the upper jaw there were only 7 hairs situated hi a single row, the two first rather further from each other than the rest. Altogether this specimen was provided with 34 hairs on the lower and 14 hairs on the upper jaw. X. Parasites. Parasites of three different sorts have been up to the present time found living upon or in B. borealis; one of these (not yet examined nor preserved) is a true ecto-parasite, one (Balanophilus uniseius) is an epizoon, and two Echinorhynchi are ento-parasites. I could find no trace of ecto-parasites on the specimens examined |
