HISTORICAL PREFACE. 
XXV 
of Vermont" (1853) paid attention to the birds of that state. Birds of Wisconsin were 
catalogued by P. li. Hoy ; of Ohio, by M. C. Eead and Robert Kennicott ; of Illinois, by 
H. Pratten ; of Indiana, by 11. Haymond ; of Massachusetts, by F. W. Putnam ; and 
various other "faunal lists" and local annotations appeared, including President Jeffer- 
son's Virginian ornithology, three-quarters of a century out of date. Dr. T. C. Henry 
and Dr. A. L. Heermann wrote upon birds of the Southwest ; Reinhardt continued ob- 
servations on Greenland birds; Dr. Henry Bryant published some valuable papers. 
The since very eminent English ornithologist, Dr. P. L. Sclater, appeared during this 
period in the present connection. The series of Pacific Railroad Reports, which were 
to culminate, so far as ornithology is concerned, with the famous ninth volume, were in 
progress; the sixth volume, containing Dr. J. S. Newberry's valuable and interesting 
article upon the birds of California and Oregon, was published in 1857. Thus the 
Cassinian period, besides being marked as already said in its broader features, was 
notable in its details for the increase in the number of active workers, tlie extent and 
variety of their independent observations, and the consequent accumulation of materials 
ready to be worked into shape and system. 
(1858-18—.) 
The Bairdian Period. — The ninth volume of the " Pacific Railroad Reports " was an 
epoch-making work, bearing the same relation to the times that the respective works 
of Audubon and Wilson had sustained in former years. A great amount of material — 
not all of which is more than hinted at in the foregoing paragraph — was at the service 
of Professor Baird. In the hands of a less methodical, learned, and sagacious naturalist, 
— of one less capable of elaborating and systematizing, — the result would probably have 
been an ordinary official report upon the collections of birds secured during a few years 
by the naturalists of the several explorations and surveys for a railroad route from the 
Mississippi Valley to the Pacific Ocean. But having already transformed the eighth 
volume of the Reports from such a " public document " into a systematic treatise on 
North American Mammals, this author did the same for the birds of North America, 
with the cooperation of Cassin and Lawrence. This portly quarto volume, published in 
1858, represents the most important and decided single step ever taken in North Ameri- 
can ornithology in all that relates to the technicalities of the science. It effected a 
revolution — one already imminent in consequence of Cassin's studies — in classification 
and nomenclature, nearly all the names of our birds which had been in use in the 
Audubonian epoch being changed in accordance with more modern usages in generic 
and specific determinations. While the work contains no biographical matter, — nothing 
of the life-history of birds, it gives lucid and exact diagnoses of the species and genera 
known at the time, Avith copious synonymy and critical commentary. Various new 
genera are characterized, and many new species are described. The influence of the 
great work was immediate and widespread, and for many years the list of names of the 
738 species contained in the work remained a standard of nomenclature from which 
few desired or indeed were in position to deviate. The value of the work was further 
enhanced in 1860 by its republication, identical in the text, but with the addition of an 
atlas of 100 colored plates. Many of these plates were the same as those which had 
appeared in other volumes of the Pacific Railroad Reports, notably the sixth and tenth 
