6 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 51 



but, according to our informant, although surrounded by a mass of 

 other bones, no attempt had been made to preserve them. 



We arrived at Fort Yukon, Alaska, the farthest point north in our 

 journey, at midnight June 23, and Rampart (see pi. I, fig. 1), the 

 limit of steamer travel, was reached the evening of June 24. While 

 here, the area drained by Little Minook Creek, Junior, where scat- 

 tered mammal remains had been found, was visited. We were shown 

 a few specimens taken out by miners, but the character of their 

 occurrence here did not justify a continued search; so, after over- 

 hauling our camp outfit and laying in a supply of provisions, we 

 loaded our canoe, and on the evening of June 28, left Rampart 

 (see pi. 1, fig. 2) for our trip down the Yukon. 1 For thirty or forty 

 miles below Rampart the Yukon flows between walls of the older 

 rocks with a current of from five to six miles an hour, accelerating 

 somewhat as the rapids are reached, near the lower end of what is 

 known as the Lower Ramparts. The first alluvial deposits en- 

 countered of any considerable thickness after passing the rapids 

 were on the right-hand bank some twelve miles above the mouth of 

 the Tanana River. Imbedded in these were myriads of small land 

 shells representing the living forms, Euconulus trochiformis Mtg. 

 and Succinca grosvenori Lea, as determined by Dr. W. H. Dall. No 

 vertebrate remains were found. 



Fort Gibbon, a military post at the junction of the Tanana and 

 Yukon rivers, was reached the evening of June 30. Here inquiry 

 was made regarding localities on the lower river points and par- 

 ticularly relating to the Palisades, better known locally as the 

 "bone yard," 2 some thirty-five miles below. We were informed that 

 scattered fossil remains were also to be found along the Tanana 

 River and its tributaries ; but, as the information was somewhat 

 indefinite as to exact localities, it was decided not to investigate the 

 reports at this time. 



The first exposures of the elevated Yukon 3 silts were observed 

 twenty miles below Fort Gibbon, where the bluffs are undermined by 

 the river for a half mile or more, and although a careful examination 

 was made for the presence of vertebrate fossils, none were found 

 either in the face of the cliff or in the talus at its base. This point 

 marks the beginning of the escarpment of which the Palisades, some 



'The day we left Rampart a small tusk of the mammoth was brought in by 

 some miners from Ray River, a locality from which Pleistocene mammals had 

 not been previously reported. 



2 So named because of the great number of fossil bones found here. 

 Spurr, J. E. : 18th Ann. Rept. I'. S. Geol gical Survey, pt. in. p. 200. 



