NO, 9 MARINE INVERTEBRATES, ALASKA — MacGINITIE 1 5 



the southwest from the Yukon, which empties into Norton Sound 

 south of Bering Strait. The Mackenzie is probably the major source, 

 and the wood is carried westward to Point Barrow by the current 

 mentioned above. However, the kelp Nereocystis, which does not 

 grow north of Bering Strait, was found on the beach at Point Barrow. 



The iceberg (pi. 7) mentioned under "Ice" must have come either 

 from below Bering Strait or from the Canadian Archipelago ; it could 

 not have come from Greenland, if the theories presented above are 

 correct. 



A few facts regarding the currents in the vicinity of Point Bar- 

 row have been ascertained. Along the shore from the Point to the 

 southwestward the prevailing current is northeast; to the east it is 

 northwest. These two currents meet off the Point and flow north- 

 ward, or, more correctly, north-northeast, for the current to the 

 northeast is the stronger, having at times a speed of 3 miles an hour, 

 or more. They are not steady and are somewhat subject to change 

 by winds. In fact, either may be completely reversed, in which case 

 they are never so strong. 



At times in going from shore directly to sea, three definite currents 

 were encountered in succession : first, a slow southwest current per- 

 haps half a mile in width ; next, a strong northeast current 6 or 8 

 miles in width ; and then a slow westward current 10 or more miles 

 offshore. The extent of the latter was not determined. Many times 

 it was necessary to give up dredging because the current was stronger 

 than winds of 15 to 20 miles an hour and would set the boat at right 

 angles to the wind and broadside to the waves. This occurred espe- 

 cially during offshore winds. 



That all water movement is in general to the northeast can be veri- 

 fied by reference to U. S. Coast and Geodetic Survey map 9445, which 

 shows that the ocean bottom to the north and east of Point Barrow 

 is very shallow, owing to the deposition of materials from the eroding 

 shores, for a long distance oceanward. 



As mentioned above, the point at Point Barrow has washed back 

 28 feet in the last four years. At this rate it is reasonable to suppose 

 that the land extended 504 feet farther north in 1880. That it actu- 

 ally did is borne out by the fact that there is now nothing left of the 

 village of Nuwuk, which was inhabited in 1880, but the remains of 

 two sod houses. 



Dall, in his report of 1882 (p. 327), corroborates the above observa- 

 tions regarding currents. He states that the currents along the coast 

 from Point Barrow westward are to the northeast with a velocity of 



