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same individuals have been observed to return annually to the sanie bays and fiords " (p. 9). The species is, for some reason, adapted to certain very special conditions; since it never leaves that part of the sea which is filled with drift ice, and more or less closed by great masses of ice." It thus migrates south in the winter and north in the summer. It cannot seek seclusion further north because the ice-conditions would not be right; nor can it go further south, for the same reason. Since it does not habitually extend further south than latitude 65° 25′ it is doubtful whether the whales of the west coast of Greenland (Davis Straits) ordinarily had any communi- cation with those of the east coast; the conditions to the north of Greenland being far too severe to permit even a Greenland Whale to choose that route. It might thus follow and perhaps has actually followed-that the extermination of the Greenland Whale to the east of Greenland would be final; or at any rate that the chance of recolonisation from Davis Straits would be very slight.

The migration of the Greenland Whale is further considered by T. Southwell (3), who gives two maps (p. 400; plate xii., opposite p. 408) showing the results he had arrived at with regard to the routes of migration, based on information obtained from David Gray and other whaling captains. These maps indicate different routes for the autumn and spring migrations—as indeed would necessarily be the case in any species which follows the edge of the ice; while one of them (plate xii.) indicates a route for the old males different from that of the females and young males, in both the autumn and the spring migrations. If other species which it may be desired to protect have any similar habits of segregation, it may be a most important fact in connection with the search for effective protective measures.

The migration of whales in general must be largely dependent on the distribu tion of the food-supply. In the case of the whalebone whales, the food consists largely of relatively small animals like certain pelagic Crustacea and Molluscs (Pteropods); but also, in some species, of Fishes. Any causes which make the distribution of the food different at different times of year will produce an effect on the movements of the whales.

Although a whale which is feeding by straining the water through its baleen- fringes cannot exercise much selection as to the kind of organisms which are retained in its mouth, it is well known that the species of whale are not alike in their pre- ferences. Thus, the gigantic" Blue Whale," or Sibbald's Rorqual, is found to be feeding exclusively on Kril" when it appears on the Norwegian coast in the summer (Collett (9) p. 593).

consists of an enormous assemblage of very "Kril" small Crustacea (Euphausiide). Collett states that as much as 12 hectolitres of "Kril" have been found at one time in the stomach of a large Blue Whale; and some idea of the quantity indicated is given by the calculation that 12 hectolitres of pure water would weigh more than one ton. The Lesser Rorqual, on the other hand, appears to be largely a fish-eater, consuming Whiting and other Gadidæ, as well as other fishes. The "Common Rorqual" lives partly on pelagic Crustacea, &c., and partly on fishes. Enormous numbers of Herrings have been taken from the stomachs of whales belonging to this species. Rudolphi's Whale is found to be feeding principally on two species of small Crustacea when it is taken off the Norwegian coast. The Humpback is believed by Collett (p. 618) to feed on different food at different times of year. Thus, on the Finmark coast it often devours very large quantities of fish ("Lodde "Mallotus); while in June and July it eats principally Kril," or Euphausiid Crustacea. At certain periods the Herring is an important

constituent of its diet.

The movements of the floating flora and fauna of the sea ("Plankton ") are dependent on causes which are but imperfectly understood; but it is evident that they are largely dependent on ocean-currents, which again are closely connected with questions of temperature and salinity. It may be explained, in this connection, that the estimation of the amount of salts in a given volume of sea-water forms an important part of modern oceanographical work. Greater evaporation takes place in the tropics than at the poles, where, moreover, the water may be considerably diluted by the thawing of ice and snow. Equatorial water has the higher salinity; and the amount of salt in a sample may thus show whence that water has been derived.

It would probably be a mistake to suppose that any species of whale subsists entirely on a few species of plankton-organisms, though it may exhibit a decided preference for them. But the movements of a whale which prefers Whiting, for instance, are likely to be different from those of one which feeds on "Kril "; and the examination of the occurrences of different species in particular localities may be found to have a very definite relation to the presence of suitable food.

Thus,

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according to Collett (9), the Lesser Rorqual (p. 564) and the Common Rorqual (p. 571) are found off the Norwegian coast at all times in the year. The latter is probably a plankton-eater which takes fish, available at almost any time, when it cannot get a sufficient supply of plankton. But when it has the choice, it prefers the Crustacea (pp. 581, 582). The Blue Whale (Sibbald's Rorqual), on the contrary, seldom appears on the Norwegian coast before the end of May or the beginning of June; and this is the time of year when pelagic Crustacea become sufficiently numerous to support it in that locality (p. 588). Rudolphi's Whale, which similarly feeds on Crustacea, is also a summer whale in Norway (p. 597).

The records of any whaling station will show that whales are to a large extent migratory animals, though the above instances will prove that all species are not alike in the character of their migrations. For information with regard to the whaling stations reference may be made to Mr. Burfield's Reports (8, 7), and to the papers by Mr. R. C. Haldane in the "Annals of Scottish Natural History," published during the last few years.

But, admitting that whales migrate, it becomes a very important question to decide what is the extent of their movements. In the case of a species such as the Sperm Whale, for instance, known to inhabit a wide area, does the same individual spend part of its life in the North Atlantic and another part in the South Pacific, or is it merely the species that has a wide distribution?

This is a question on which information is specially required; and an answer cannot at present be given to it. It is stated that the same species of Rorqual is larger on the European side of the Atlantic than on the American side,* and this In view of may be a significant fact, indicating the existence of separate herds.

the problem of the southern whales, it is specially important to know whether the same herds are hunted in Antarctic waters during the summer and on the coasts of South America, New Zealand, South Africa, &c., during other parts of the year.

It can hardly be necessary to summarise the facts with regard to Antarctic whaling, since these are readily accessible to the Colonial Office. I quote one state- ment, taken from an Annual Report (11) of the Board of Agriculture and Fisheries. On p. 54 of this Report will be found the statement that

"The number of whales captured annually in southern waters increased from 183 in 1908 to 12,635 in 1911."

It may be noted that the Report goes on to point out that the whaling industry

in 1912 was not everywhere so successful as had been anticipated, "though pursued with considerable vigour and in new areas."

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It is impossible to avoid seeing an analogy between what is taking place off South Georgia and the neighbouring Antarctic localities and what has happened elsewhere in the world. The parallel is perhaps closest with the Greenland Whale fishery in which, on three separate occasions-first off Spitzbergen, next in Davis Straits, and last in the North Pacific-enormous numbers of whales were discovered. The industry had a period of great prosperity in each case, the number of vessels being continually augmented until the fishery began to prove less profitable. From this point the decline has been rapid, so that the species in question has been exterminated in many of the localities it used to frequent, and apparently barely survives in the others.

In southern waters, indeed, we are still in the period of prosperity. But taking into consideration the more deadly nature of modern whalers' weapons than of those which have been almost successful in the extermination of the Greenland Whale, it cannot be disputed that the present rate of destruction of whales in the south gives rise to grave anxiety.

WHALES AND WHALING (REFERENCES).

(1) GOODE, G. BROWN-"The Fisheries and Fishery Industries of the United

States."

(a) Section I. Natural History of Useful Aquatic Animals, with an Atlas of two hundred and seventy-seven plates. U. S. Commission of Fish and Fisheries. Two Vols. (text and plates). Washington, 1884.

(b) Section V. History and Methods of the Fisheries in two Volumes, with an Atlas of two hundred and fifty-five plates. Vol. II. U. S. Com- mission of Fish and Fisheries. Two Vols. (text and plates). Washington, 1887.

• Of. (7) pp. 16, 29 (8øp. copy).

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