104 Dr. U. W. Shufeldt on the 



did in those days. Improvement over early authors was very 

 evident, however, and many palpable errors were rectified. 

 From such beginnings the science has grown up, authors and 

 classifiers being more and more numerous with each succeeding 

 generation. Some used one set of characters and some 

 another; but it is to be distinctly noticed that the previous 

 taxonomic schemes have always influenced their followers in 

 later years. Merrem, who in 1812 was perhaps the first to 

 publish a systematic arrangement of the groups of birds, was 

 doubtless influenced by all that had been accomplished prior 

 to his time, as the work of Nitzsch in pterylography, Cuvier 

 in structure, and Linngeus and Ray in a number of external 

 characters. His scheme was a solid contribution to the classi- 

 fication of birds, based as it was upon a variety of anatomical 

 characters, as those drawn from the sternum, those from the 

 feathers, those from the osseous system, and those from 

 other parts, as the bills and feet. In fact Merrem took a long- 

 step in the direction of the truth, or, rather, in the discovery 

 of the true relationships of birds in nature. 



De Blainville quickly followed Merrem, and again re- 

 arranged the avian scheme of classification, fascinated as he 

 was by the characters presented on the part of the body of 

 the sternum. In some directions further advancement was 

 evidenced, however, and this advancement later on was power- 

 fully increased by the labours of Nitzsch, who brought into 

 play the arterial system, the song-muscles, the nasal glands, 

 and other morphological features. 



Thus, from the time of Nitzsch down to the present day 

 the classification of birds has gone through many changes 

 and many phases at the hands of the ornithologists of the 

 succeeding generations as they have passed. The greatest 

 advances have been made since the scientific demonstration of 

 the law of organic evolution and the derivation of birds became 

 known, and these by the men who have studied the subject 

 from that standpoint. Were it possible for us now to know 

 the complete biology of every bird-form that has existed upon 

 the earth since birds as birds came into existence, there would 

 be among ornithologists an agreement of opinion upon their 

 classification, the world over, within a twelvemonth. If half 

 the species that have existed were known, the scheme would 

 almost work itself out. As it is, we probably see to-day in 

 the world's avifauna but a paltry remnant of that enormous 

 and unknown host, and it will be generations yet to coaie ere 

 there will be a consensus of opinion upon the affinities of this 

 puzzling and very homogeneous group of vertebrates. When 

 compared with other major groups of animals, either verte- 



