42 MARINE MAMMALS OF THE NORTH-WESTERN COAST. 
fins and about the abdomen. The posterior edge of the hump, in many examples, 
is tipped with pure white. The megaptera varies more in the production of oil 
than all others of the rorquals. We have frequently seen individuals which yielded 
but eight or ten barrels of oil, and others as much as seventy- five; the length of 
the animal varying from twenty-five to seventy-five feet. Most of these variations 
may be attributed to age and sex, as the female with a large cub becomes quite 
destitute of fat in her covering. These animals, more especially the smaller or 
younger ones, are infested with parasitic crustaceans (Cyamus sttffusus), which collect 
in great numbers about the head and pectorals ; or, in case there are any wounds 
upon the body, these troublesome vermin are sure to find them. On the coast of 
California, in 1856, we captured a whale of ordinary size, which had many patches 
of these parasites united almost in one mass upon that portion of the body which 
was exposed when the animal came to the surface, and when "cut in" it proved 
to have what is termed a "dry skin," the blubber being destitute of oil; this was 
attributed to the abundance of these troublesome parasites. The Humpback has 
also the largest barnacles adhering to, or imbedded in, the epidermis, about the 
throat or fins. The habits of this whale — particularly in its undulating movements, 
frequent "roundings," "turning of flukes," and irregular course — are characteristic 
indications, which the quick and practiced eye of the whaleman distinguishes at a 
long distance. Even when beneath the surface of the sea, we have observed them 
just "under the rim of the water" (as whalemen used to say), alternately turning 
from side to side, or deviating in their course with as little apparent effort, and as 
gracefully, as a swallow on the wing. Like all other rorquals, it has two spiracles, 
and when it respires, the breath and vapor ejected through these apertures form 
the "spout," and rises in two separate columns, which, however, unite in one as 
they ascend and expand. When the enormous lungs of the animal are brought 
into full play, the spout ascends twenty feet or more. When the whale is going 
to windward, the influence of the breeze upon the vapor is such, that a low, bushy 
spout is all that can be seen. The number of respirations to a "rising" is exceed- 
ingly variable : sometimes the animal blows only once, at another time six, eight, 
or ten, and from that up to fifteen or twenty times. 
Although the Humpbacks are found in every sea and ocean, our observations 
indicate that they resort periodically, and with some degree of regularity, to partic- 
ular localities, where the females bring forth their young. It seems, moreover, that 
large numbers of both sexes make a sort of general migration from the warmer 
to the colder latitudes, as the seasons change. They go north in the northern 
hemisphere, as summer approaches, and return south when winter sets in. 
