16 TT. S. NATIONAL MUSEUM BULLETIN 217 



a height of 15 or 20 feet, in others they are only a few feet high. A 

 few small cottonwoods occur in occasional and restricted areas and 

 a few alders are found at Akvalutak Creek. 



Northward in the John Eiver Valley the traces of glaciation be- 

 come more apparent, and the upper John and Anaktuvuk Rivers lie in 

 an obvious glacial cut trough about 3 or 4 miles wide between steep 

 mountain walls of much dissected metamorphic rocks. No superficial 

 ice now remains permanent in the Pass, but a small mass of ice near 

 tree line in the upper John Valley, not now evident, was reported 

 by Schrader (1904) as of glacial origin. 



Along Anaktuvuk Pass the mountains rise steep and sharp to 5,000 

 or 6,000 feet. Through their walls enter occasional narrow and pre- 

 cipitous valleys much eroded by water since their initial formation by 

 tributary glaciers from former high snow fields. Now the sparse snow- 

 fall outlasts the hot June sun in only a few places. With its meager 

 precipitation this country has some resemblance to the desert region 

 in the southwestern States. The wide fans of boulders and gravel at 

 the foot of the tributary streams attest the occasional power of ancient 

 slides and occasional flood flow, and the appearance of lateral moraines 

 on the mountain walls west of Kalutak Creek suggest that the ice 

 levels of the glacier may have been 1,000 feet above the present floor 

 of the John River Valley. The northern margin of the mountains 

 rather sharply forms a mountain line, north of which only an occa- 

 sional elevation rises to 2,000 feet among generally long-sloping 

 smooth hills. 



At the base of the steep side walls of the valley the talus slopes end 

 at a level a few hundred feet above the valley floor. Below that level 

 the gently sloping terrain is often dry and sparsely covered with 

 short vegetation over the occasional, well drained areas of gravel. 

 More often the surface is wet and irregularly spotted with 

 hummocks of sedge clumps called niggerheads. The small tributary 

 stream beds are often elevated upon fans of their own detritus, into 

 which they cut annually varying channels. These are frequently lined 

 with willows that are a few feet high near the mountain walls and up 

 to 12 or 15 feet high in occasional stands along the river flats, where 

 the basal trunks may be 5 or even 6 inches in diameter. 



From the junction with the larger east fork ( Anaktiktoak) just be- 

 low Kangomavik, the Anaktuvuk meanders north in the mountains 

 for about 15 miles through a flat valley floor of sand and gravel among 

 small moraines, leaving several cutoff, or oxbow, lakes (see map, fig. 

 4) . On the tundra adjacent to the river are many marshes and small 

 lakes, some of which are of the strange but not unusual arctic type 

 resembling limestone sinks, with steep sides cut deeply into the per- 



