ee | Patmer, In Memoriam: Wells W. Cooke. 1S 
for North America (p. 8). While he rejected Middendorff’s term 
“‘isepipteses’ proposed in 1855 to denote lines of equal flight or 
simultaneous arrival, he adopted precisely the same thing in his 
maps prepared for the use of the Committee on Regulations on 
Migratory Birds in 1913, and published them as ‘isochronal lines’ 
in 1915.1 Although he paid scant attention to the work of banding 
birds, only a few weeks before his death he had occasion to alter 
materially his views regarding the routes of certain species of ducks 
on account of data derived from this source. But it is greatly 
to his credit that he was ever ready to modify his opinions in the 
light of new data or reject an old hypothesis which was made 
untenable by new and more complete records. 
Cooke’s principal contributions to ornithology were undoubtedly 
his great work in collecting, arranging and preparing for use the 
immense mass of records concerning the migration and distribu- 
tion of North American birds, in giving instruction on these sub- 
jects through publications, lectures, and personal advice, and in 
stimulating interest and codperation in bird study and especially 
in bird migration — in short in the application of existing informa- 
tion to the actual solution of certain ornithological problems. 
Suddenly at the opening of the spring of 1916 he was called upon 
to lay’aside his work. He hadrecently passed his 58th birthday 
and apparently had several years of active and useful work ahead. 
But just at the height of his activity and usefulness when he was 
hoping to see the early completion of several projects in which he 
was interested, his hand was stayed and the pen which had long 
been overworked was laid aside forever. Rarely in the annals of 
ornithology has the advent of what has been called the greatest 
adventure in life come under more appropriate circumstances. 
On Monday, March 20, it was my privilege to accompany Professor 
Cooke and his daughter on what proved to be his last outing. 
Swans had been reported on the Potomac just below Alexandria 
near Jones Point where about a dozen of the stately birds were 
found feeding and swimming about some distance from the shore. 
Professor Cooke was greatly interested in them and remarked that 
it was many years since he had seen his last live wild swan in the 
1 Bull. 185, pp. 36, 38, 42. 
