LIST OF TREES AND SHRUBS. 319 



Island. Mr. Douglas found it growing to the height of 170 

 feet, with a trunk 40 feet in circumference. 



Juniperus communis extends from the vicinity of the Arctic 

 Sea to the New England States and Newfoundland. It pro- 

 duces berries freely on elevated grounds within the arctic circle. 

 J. prostrata (Persoon), repens, vel humilis aliorum, is considered 

 by Sir "William Hooker to be a variety of J. sabina, which 

 includes the J. virginiana. It has always the prostrate form 

 in Rupert's Land, and was observed within the arctic circle, 

 1,000 feet above the sea, associated with the preceding, and 

 bearing fruit. Dr. Gray informs me, that it is not found in 

 this prostrate flagelliform condition south of New York and 

 Northern Pennsylvania. The ordinary J. virginiana, red cedar 

 or savin, ranges to the furthest limits of Texas, and to the 

 country about Santa Fe and Tampas Creek, which is elevated 

 from 3,000 to 5,000 feet above the sea. Col. Emory found it 

 on the 35th parallel, at an altitude of from 6,000 to 7,000 feet, 

 in form of a large tree. Taxus canadensis, American yew or 

 ground hemlock, grows in Massachusetts and Newfoundland, 

 and on the borders of the great lakes northwards to the south- 

 ern slope of the Saskatchewan basin. It is a very pleasing 

 underwood, with an almost herbaceous aspect, which grows 

 thickly under the shade of many kinds of trees. On the canoe 

 route it never assumes the tree form ; but in the valley of 

 Oregon Mr. Douglas found yew trees as large as those of 

 Europe. 



The following table is founded on Sir William J. Hooker's 

 Flora Boreali- Americana. Since the publication of that 

 work, Sir George Back's voyage down the Thlewee-choh, 

 Messrs. Dease and Simpson's through the Arctic Sea, Mr. 

 Rae's from York Factory to Repulse Bay, the voyage 

 detailed in the preceding pages, a list of Nova Scotia 

 plants contributed by Mr. Dawson of Pictou, a collection 



