42 PUBLICATIONS OF SPENCER F. BAIRD. 



1857. Baird, Spencer F. — Continued. 



throughout of the works and articles of "Wagner, "Waterhouse, Gray, Brandt, Burmeistt r, 

 Keyserling and Blasius, Giebel, Richardson, Agassiz, Englcmann, and others, as eniimer 

 atod in the synonymy and list of authorities. To the labors of Messrs. Audubon and Bacli- 

 man, however, either singly or collectively, are acknowledgments especially due forwluit- 

 ever facilities may have previously existed for the preparation of a report on American maui- 

 mals. The necessity or propriety of such a report is only to be found in the fact that, wh<u 

 the crowning work of these gentlemen, ' The Viviparous Quadrupeds of North America,' 

 was prepared, the materials at their command were far less extensive than have been at 

 mine, and that many species, which they could only examine in the museums of London, Paris, 

 Berlin, and Leyden, are now to be found in the Smithsonian collection in a profusion of speci- 

 mens of the most satisfactory and perfect character. 



"An apology is necessary for the delay which has taken place in the completion of the 

 general reports on the zoology of the Pacific Railroad surveying parties. This has arisen 

 from the fact that, from the first organization of these expeditions, in the spring of 1853, 

 nearly to the present time, one or more has been in the field, and engaged in fresh examina- 

 tions ; so that until fill the specimens expected were received, the general systematic account 

 of zoological results could not conveniently be prepared. The examination of the materials 

 was actually commenced early in 1855, and many of the articles -written in that year in 1856. 

 "With the continuous accession of additional specimens, it became finally necessary to re- 

 write, alter, or extend all that had been prepared prior to the present year (1857). It is to 

 this that the frequent want of uniformity is due, the time allowed not being sufficient in 

 many cases to permit the reworking of the whole matter. The measurements of the speci- 

 mens were at first made in inches and lines, but that of hundredths was finally adopted ; it is 

 to this fact that the presence of the two different divisions of the inch is attributable, it not 

 being convenient or possible to make the measurements conform throughout, as would have 

 been desirable. 



" It is, perhaps, unnecessary to state that the matter of the present report is entirely orig- 

 inal throughout, the few cases in-which extracts from other authors are made being so 

 indicated. "With very few exceptions, all the references in the synonymy have also been 

 personally made and verified. Where this was not possible, the synonym is inclosed be- 

 tween quotation marks. 



"In explanation of the too frequent occurrence of typographical errata in the body of this 

 report, it is proper to state that, owing to various circumstances, the work was necessarily 

 passed through the press with a rapidity probably unexampled in the history of natural-his- 

 tory printing, allowing very little opportunity for that critical and leisurely examination so 

 necessary in conectiug a work of the kind. For most of the time the proof has been furnished 

 and read at the rate of twenty-four to thirty-two pages per day, nearly four hundred pages hav- 

 ing been set up, read, and printed during the first half of July alone. The same cause has 

 also interfered with the preservation of perfect uniformity of arrangement and detail through- 

 out. In some cases, accidents to the fonn while on press have caused the loss or transposi- 

 tion of letters, words, or paragraphs; as, among others, the exchange of characters of Orders 

 yill and IX, on page 1, referred also to on page 625. For excuse of errors in the use of 

 technical terms, in the formation and inflection of scientific names, find for all other short- 

 comings, the writer can only thiow himself upon the kind indulgence of his readers, partly 

 in consideration of the fact that, owing to the urgent necessity for a speedy completion of 

 the volume, no time was allowed for any revision of the manuscript as a complete work, nor, 

 indeed, of its separate portions, and that for much of the time the preparation of much of 

 the manuscript was only a few hours in advance of its delivery to the compositor. 



"A few words in explanation of the plan adopted in preparing the articles of the present 

 report may not be out of place. I have usually made the entire detailed description of the 

 species from one particular specimen, often indicating it by number, mentioning afterwards 

 the variations presented from this type by the others before me. The specific diagnoses 

 alone contain a combination or selection from the characters of several specimens. The nimi- 

 bers attached to the specimens, as enumerated, are those which they bear in the Smithsonian 

 Museum Catalogues. Each class of animals has its separate catalogue and succession of num- 

 bers, from 1 upwards, in this series, the same number being never used twice for different 

 objects in its class, and thus constituting an essential part of the specimen. There is also a 

 Bpecial catalogue of the osteological collections. Thus, the skin of a mammal will have one 

 number, and its skull, if separated, another; each specimen having both numbers attached, 



421 

 ita own as numerator of a fraction. Thus, when a skull is labeled or entered j^^g, it is to be 



understood that 421 is its number as entered in the catalogue of skins (or entire specimens 

 in alcohol), while 1149 is the number of the skull as entered in the osteological catalogue. 



1149 

 The skull itself would in this case be marked ^.2^ . 



