1870.] Botany. 101 



increase beneath the bark by the formation of concentric rings of 

 wood, from the number of which the age of the tree can be deter- 

 mined. This had, however, also been already observed by Da Yinci, 

 and is recorded in passages in the same work. 



Arctic Flora. — Dr. Berthold Seemann discusses in the ' Journal 

 of Botany ' the question whether vegetation extends to the North 

 Pole, supposing land exists there. He answers the question in the 

 affirmative, maintaining that excessive cold in winter exercises but 

 a limited influence upon a vegetation which, like the Arctic, enjoys 

 the protection of a thick covering of snow, and is besides in a state 

 of inactivity. The temperature of the summer during the months 

 of July and August has by far the greatest share in the distribution 

 of vegetable life in the northern regions ; and the lowest tempera- 

 ture during those months is not found in the most northerly point 

 yet reached by any exploring expedition, but in Winter Island on 

 the eastern shores of the Melville Peninsula, where the mean tem- 

 perature during July and August ranges between 34° and 36° F. 

 That spot, which may be called the phytological pole, is nevertheless 

 covered with vegetation ; and, knowing as we do, that plants do grow 

 not only on a frozen soil, but even, as in Kotzebue Sound, on the 

 tops of icebergs, there is no reason to suppose that the terrestrial 

 pole is destitute of vegetation. The most northerly berry-bearing 

 plant yet recorded is Vaccinium Vitis-Idsea, or the cranberry, 

 gathered in Bushman Island, on the north-west shore of Greenland, 

 by Captain W. Penny, or in latitude 76° N., longitude 66° W. 

 The most northerly berry-bearing genera are Vaccinium, Oxycoccus, 

 Bubus, Cornus, and Empetrum. It is stated that occasionally 

 berries ripen in Lapland. 



Vegetation of Howe's Island. — The flora of this island, 300 

 miles from Sydney and 500 from Norfolk Island, has been investi- 

 gated by Mr. Charles Moore, and is found to resemble much more 

 closely that of the latter island than of Australia. Its situation is 

 31° 36' S. lat., 159° 5' E. long.; it is 4J miles in length and 1J- 

 in breadth, possesses two mountains about 2500 feet high, and is 

 entirely covered with vegetation, with no barren spots except the 

 coast and the precipitous cliffs. The indigenous species are very 

 few, most of them being peculiar to the island and undes r, ribed. Of 

 Endogens there are four species of Palm, all undescribed and of 

 great value to the natives ; two species of Pandanus ; three Grasses ; 

 two Orchids ; a Juncus ; a Smilax ; one species belonging to Iridacese, 

 one to Amaryllidacede, three to Cyperacese, and one to Comme- 

 lynacese. All the clearings are, however, covered with introduced 

 European plants, including the couch-grass. Among Exogens, the 

 Australian Proteacese and Leguminosde are entirely wanting; 

 Epacridde and Myrtacese, so abundant in Australia, are represented, 

 the former by a single species, a tree 30 or 40 feet in height, grow- 



