2^2 DR. HOOKER ON THE DISTRIBUTION OF ARCTIC PLANTS. 
to the Alps and Pyrenees, Carpathians, Balkan, and Tauria (inclusive) in Europe, and to the Caucasus, 
Altai and Soongaria (inclusive) in Asia. 1. Europe to the Alps. Here A. implies that the plant in- 
habits the Alps, or Pyrenees, or Caucasus ; and N. that it is a more northern plant, not advancing south 
nt dVrmany or Central Russia, in many cases not south of Scandinavia. 2, Asia to the Altai, Soongaria 
and Dahuria; the eastern limit of this zone is supposed to be the Jablonoi range, and the western, 
the Obi River. 3. Eastern Asia, from Behring's Straits to the south of Japan, including Mantchuria, 
Kamtschatka, the peninsula of Ochotsk, North China, and the neighbouring islands of Japan. This 
district presents a transition zone between the Asiatic and American floras, and were it better explored 
might possibly be incorporated with the latter, in the higher latitudes at any rate. 
III. American Distribution* — 1. North-west America includes the band of country from the 
Rocky Mountains to the Pacific. This is for the most part a very mountainous area, presenting two floras, 
the Columbian, which extends south to the Oregon; and the Californian, which extends north to that 
river, and inland to a considerably higher but still unknown latitude. Being unable to define the limits 
of these two floras, I have not indicated to which the arctic plants belong, but here, as in the following 
column, an It. indicates that the species inhabits the Rocky Mountains. 2. North-east America. This 
includes all temperate North America, from the Rocky Mountains to the Atlantic. In this column the 
letter C. indicates that the species is Canadian, but does not enter the United States ; L. that it is con- 
fined to Labrador, R. to the Rocky Mountains, and W. that in the United States it has been only found 
on the White Mountains of New Hampshire, or on other high mountains of the Eastern States. 3. Tro- 
pical America. With few exceptions the arctic plants found in this province are confined to the temperate 
and alpine regions of the Cordillera from Mexico to Peru inclusive. M. signifies that it has been found 
in, but not south of, Mexico. 4. Includes Extra-tropical South America and its islands. 
IV. South Europe and Africa.— 1. Europe south of the Alps, Asia Minor, the Canary Islands, and 
Africa north of the tropic. In this column are included the plants of the Spanish and Italian peninsulas, 
Dalmatia, &c, Greece, and both Turkeys. Of these countries, Asiatic Turkey, or Asia Minor, should 
perhaps have been ranked in the Asiatic column with Persia, &c. ; but it contains so very many European 
plants that are not found further east, that I have included it here. The letter A. in this column indi- 
cates that the plant actually crosses the Mediterranean to North Africa, and is found in Algeria, Egypt, 
the Canary Islands, or the mountains of Abyssinia*. 2. South Africa, from the Cape of Good Hope to 
the tropic. 
V. Central and South Asiatic Distribution.— 1. Persia, Tibet, and the Himalaya Mountains. 
In this column the letter H. indicates that the species inhabits the Himalaya or Tibet. 2. Tropical Asia. 
This includes all India south of the Himalaya, and especially the Khasia* mountains of Eastern Bengal 
the mountains of both peninsulas of India, of Ceylon, and of Java. 3. The last column is confined to 
Australia, New Zealand, and the antarctic islands to their south. 
The map that accompanies this paper is reduced from the latest Admiralty chart of the north polar 
regions (that of 1860), by permission of Captain Washington, R.N., Hydrographer of the Admiralty. 
The isothermal lines are taken from Professor Dove's work < On the Temperature of the Globe/ translated 
by Mnjor-General Sabine, and printed by the British Association for the Advancement of Science in 
1 - >3. I have^selected what appeared to me the seven most instructive isotherms; namely, the annuals of 
? o 1 5 and 32 ° ; the tW ° J,me isotherms of 32° and 41°, and the two September isotherms of 32° 
and 41 ; these two months answering respectively to the flowering and fruiting seasons within the arctic 
circle. ° 
ak, !°, ^ X T ^ EU T an I,kntS haVC beeU f ° Und hl Tr °P ical Afri <*> that I have not devoted a column to it. 
About twenty, however, have been identified either by Achille Richard, by the namers of the Sehnnper's and Kotscby's 
It' Z f. w-nT m ii " HerbariUm - Even ° n <*""» P "*> * —tain on the isolated island of Fer- 
.uuido Po, 10,600 feet high, arcttc plants have been found by Mann, the collector for Kew, Deschampsia ca,pitosa, 
achypod 
cula £uropaa 
