162 Cameron, The Ferruginous Rough-leg. [April 



which despite its modest name is an immense laccoHth constituting 

 an isolated spur of the Highwood mountains, — 2600 feet above the 

 prairie. In reality the so called ' Chalk Cliffs' consist of an outcrop 

 of white sandstone, chiefly in the centre of a range of grass-covered 

 hills whose green summits rise in strong contrast above the white 

 corrugated rocks. This sandstone stratum has been worn into a 

 series of perpendicular cliffs, pure white above, but stained light 

 brown below by lignitic matter and projecting spurs are carved 

 into fantastic pinnacles and mounds. One promontory in particu- 

 lar is a regular sawtooth ridge. The nest here shown is poised 

 upon the apex of a pillar which terminates a knife blade pro- 

 jection of 3537 feet elevation, and suggests in some photographs 

 the prow of a ship. As there is a sheer vertical descent on three 

 sides, and the surface of the connecting ridge suddenly breaks off 

 leaving a wide fissure in the rock between it and the nest it is a 

 task of no small difficulty to reach the latter and one best suited 

 to a sailor or a cat. It can only be accomplished by approaching 

 the eyrie from above, and then crawling along the ledge, when by 

 dropping into and crossing the gap, which is well shown in the 

 photograph, the nest can be attained. Mr. Felton, making light 

 of the danger, climbed frequently to the nest, and made numerous 

 exposures with a small Kodak, at the range of a few feet. The nest 

 was four feet in height, and three and a half feet in diameter, and 

 was higher than any Montana eyries of the Golden Eagle (Aquila 

 chrysaetos) known to me, which species had also nested in the 

 'Chalk Cliffs.'^ The hawks carried green alfalfa to the nest for 

 decorative purposes, and Mr. Felton noticed a fresh supply there 

 on three separate occasions. When found on May 18, the eyrie 

 contained three newly hatched young, but only two reached 

 maturity, as one of the nestlings disappeared on July 9, when 

 fifty-two days old. Mr. Felton conjectured that it had been blown 

 out of the nest by a violent thunder storm, but the two stronger 

 birds might have ejected their weaker brother. In any event, the 

 outcast would soon have been picked up by some four footed or 

 winged marauder. The two remaining fledglings permanently 



1 In his recently published ' History of The Birds of Colorado.' Mr. W. L. 

 Sclater mentioned (p. 182) a Golden Eagle's nest which measured 'six feet In 

 diameter and nine feet high.' 



