8 CALIFORNIA ACADEMY OF SCIENCES [Proc. 4TH SER. 
In 1863 in Muséwm ad Histoire Naturelle des Pays-Bas, 
4me Livraison, Dr. Hermann Schlegel published a systematic 
monograph of forty pages on the “Procellariae,’ describing 
two new species and limiting the number of genera to three, 
thereby following a course opposite to that of Bonaparte. 
With Bonaparte and Schlegel closed the Pre-Couesian 
Period in the study of the albatrosses, petrels, and diving 
petrels. The quarried stones were now ready to be built into 
a lasting foundation by a master builder. 
THE COUESIAN PERIOD: 1866-1896 
Plate 1 
The monograph that defines the preceding and the present 
period was written by a young man who had not attained his 
twenty-fourth year, Dr. Elliott Coues, an Assistant Surgeon 
in the United States Army. This monograph was published 
in five parts in the Proceedings of the Academy of Natural 
Sciences of Philadelphia, as follows: 
A critical Review of the Family Procellaride: Part I., em- 
bracing the Procellariee, or Stormy Petrels, March, 1864, 
pp. 72-91. 
A Cnitical Review of the Family Procellaride:—Part II.; 
Embracing the Puffinee, April, 1864, pp. 116-144. 
A Critical Review of the Family Procellariide:—Part III; 
embracing the Fulmaree, March, 1866, pp. 25-33. 
Critical Review of the Family Procellariide:—Part IV; 
Embracing the A:strelatee and the Prionee, May, 1866, pp. 
134-172. 
Critical Review of the Family Procellartide ;—Part V ; em- 
bracing the Diomedeine and the Halodromine. With a Gen- 
eral Supplement, May, 1866, pp. 172-197. 
Although young in years, Dr. Coues was highly equipped 
for monographic work in ornithology. He was well grounded 
in anatomy and was familiar with the Latin, French, and 
German languages. He had been trained in the Bairdian 
methods, and already had had experience in monographing 
groups of birds. He had access to the books and specimens 
of “the Philadelphia Academy and the Smithsonian Institu- 
