522 NORTH AMERICAN FAUNA. [no. 27. 



tains, on June 4, 1904, the pistillate catkins were 1 inch in length 

 and the leaves about one-third grown. 



Salix bebbiana Sargent. Bebb Willow. 



This is one of the commonest willows, forming dense thickets on 

 the banks of the streams and in the alluvial swamps north to the 

 lower Mackenzie. Specimens were collected at various points be- 

 tween Grand Rapid and Fort Good Hope. On the upper Mac- 

 kenzie it grows to be a fair-sized tree — nearly a foot in diameter and 

 25 feet high. At Fort Simpson on May 12, 1004, the leaves and 

 staminate catkins w T ere over an inch long, being farther advanced 

 than on Great Slave Lake on June 21 of the previous year. 



Salix arbusculoides Anders. Little-tree Willow. 



Specimens referred to this species were taken at Fort Resolution, 

 Loon Island (50 miles north of Fort Resolution), Lake St. Croix, 

 Nahanni Mountains, Fort Norman, and Fort McPherson. Its leaves 

 open rather early, and were nearly full grown on the slopes of the 

 Nahanni Mountains on June (>, 1904. 



On Loon Island, which is wind swept at all seasons and where al- 

 most Barren Ground conditions prevail, the willows were stunted, and 

 the specimens collected, though mature, have exceedingly small leaves. 



This species extends north of the tree limit, and is perhaps the 

 largest species on the Barren Grounds. 



Salix chlorophylla Anders. Tea-leaved Willow. 



This willow, whose twigs are dark reddish, was common at Fort 

 Simpson. On May 12 its leaves were just starting, and three days 

 later they were half an inch in length; the pistillate catkins were 

 then over 1 inch long. 



Salix anglorum Cham. Robert Brown Willow. 



This dwarf willow was collected only on the exposed shores of 

 Great Bear Lake near Leith Point. Usually its gnarled and sparsely 

 leaved stems cling closely to the rocks, and even in the most favor- 

 able situations it attains a height of only a few inches. I took it 

 on the Hudson Bay Barren Grounds in 1900. 



My specimens were determined by P. A. Rydberg. 



Salix seemannii Rydberg. 



Willows identified as this species by P. A. Rydberg were collected 

 near Leith Point, on Great Bear Lake, and at Forts Providence and 

 McPherson. The species was abundant at the latter locality. 



Salix glaucops Anders. 



Willows referred to this species by P. A. Rydberg were collected 

 near Leith Point, on the south shore of Great Bear Lake, on August 



