Translation 2783

204
it is small, and almost triangular in shape. The snread of tne flukes - • •
is equal to about one-quarter of. the body length. 'There are tubercles
along the front edge of tae flippers -- vestiges of cuticular armour .
In specimens from the Sea of Azov these tubercles appear only on the
front edge of the dorsal fin.
The upper jaw contains from 44 to 60 teeth (most often 27 137
pairs), and the lower jaw . from 58 to 55 (most often 22 or 25 pairs).
They are set obliquely within the oral cavity, but with age they
become twisted and much abraded. The diameter of, tue teeth in the
centre of the row is about 2 mm; dley are compressed laterally and
chisel-shaped, and have a constriction between tue reot and. tue crown.
The palate is smooth, without longitudinal grooves.
The colour of the harbour porpoise may be from dark-grey to
black above,• and from white to dark-grey underneath. A dark, almost
black stripe runs from the corner of tae mouth to the flipper. Al- .
binos rarely occur.
•
There are from 62 to 66 vertebrae, and 'rom 12 to 14 pairs
of ribs.
narbour porpoises are Pound only in the northern hemisphere,
in coastal waters of the Atlantic Ocean, in tue l.ortn, 0,1tic, White,
and Barents Seas, and also in tue Sea of Azov and the Black. bea.
Occasionally they pass through the Strait of Gibraltar into the Mediterranean
Sea. In the northerh part of tue Pacific Ocean they are
found . along the coast of America from' Mexico to Alaska, including.
Point Barrow, and from tne southern part of tne Chukchi Sea along
the coast of Asia to Japan.
• Genus Globicei)hala Lesson, 1828 (Common blackfish) •
This genus contains a'single species.
•
Common Blackfish (Globice .phala melaena Traill, 1809)
lb
This species is sometime:i divided into subspecies: the common
blackfish melae .na melaena Traill, 1d09), wnicn is found in the
Atlantic Cicean (including tLe - editerranean :ea ) , t;loindian ucean,
and the soutnern part of tit: lacific ocean; and G. melaena sieholdi,"
(Gray, 1846), which is found in t.le northern part. of tn., lacific ucean.
The males are larFer tnan tae females, tne larest of each
nux me;.surin 0.5 metren and 5.0 metres re:,pectivel;i.
body lias