340 



COVILLE 



to this species. The type locality of Trautvetter's rotutidifolia is 

 given as St. Lawrence Island. 



The nearest Alaskan relative of Salix leiocarpa^ as indicated in the 

 key, is Salix fhlebophylla to which the student is referred for further 

 comments on the peculiarities of this little group of species. Salix 

 folaris also is a near relative. Salix hehringica Seemen, recently 

 described ^ from a specimen collected at " Luetke-Hafen," ^ near Bering 

 Strait, agrees in most respects with this species. Its leaves, however, 

 are larger, lo by 14 mm., and it is described as having an erect bushy 

 growth. The specimen on which the description was based was a 

 pistillate twig 17 cm. in length. 



23. SALIX RETICULATA L. Netleaf Willow. 



Plate xLii. 



Salix reticulata L. Sp. PI. 2 : 1018. 1753. 



Salix orbicularis A-iiUKKs. in DC. Prod. 16': 300. 1S68. 



A prostrate willow very distinct in its characters, as given in the 

 key, from any other Alaskan willow. Its filaments, in the staminate 

 catkins, have their basal portion densely pubescent ; in all other 

 Alaskan willows the filaments are glabrous throughout. The scales 

 of the pistillate catkins are broadly deltoid-obovate, dark, or sometimes 

 pale, red-purple in color, smooth on the outside, or slightly hairy at 

 the base, pubescent with short curled hairs on the inside, these hairs 

 projecting only slightly beyond the end of the scale. In most willows 

 the hairs on the catkin scales are long, straight and silky, commonly 

 equaling the scale in length. Usually the leaves at maturity are en- 

 tirely devoid of hairs, but sometimes, notably in the specimens from 

 the St. Matthew Islands, the long, straight silky hairs frequently pres- 

 ent on young leaves persist on both surfaces till the leaves are full 

 grown, usually disappearing in age. The species is widely distributed 

 in North America in arctic and arctic-alpine situations and occurs also 

 in Asia and Europe. In Alaska it stretches over the Arctic zone, ex- 

 cept in the extreme north, and southward it occurs at timber line on 

 the mountains from the Juneau region to Kadiak Island, and westward 

 to the Aleutian Islands. 



Alaskan specimens have been examined as follows : 

 Juneatc.—^Qa.r the summit of the mountains east of Juneau, at an 

 elevation of 3000 feet, F. A. Walpole, 1900 (No. 1233). 



1 Seemen, Engl. Bot. Jahrb. Beibl. 52 : 6. 1S95. 



2Lutke Harbor, I am informed by the Rev. Sheldon Jackson, general agent 

 of education in Alaska, is the anchoring place for vessels behind the sandspit in 

 • St. Lawrence Bay, Siberia. 



