MUSEUM OF COMPARATIVE ZOOLOGY. 163 



in reference to these variations arc given in this part, but a lame pro- 

 portion are recorded in the general and revisionary notes of Part IV. 

 The conclusions arrived at, it may be here premised, are mainly the fol- 

 lowing: (i.) That the majority of nominal species originate in two 

 principal sources of error; namely, (a) an imperfect knowledge of the 

 extent and character of individual variation, and (b) of geographical 

 variation. ('-.) That this imperfect knowledge is mainly due to the 

 neglect of zoologists to study with sufficient care the common species 

 of their respective countries, whence has arisen a faulty method of in- 

 vestigation and erroneous ideas respecting species and specific charac- 

 ter-. (3.) Instead of the method at present pursued by a large school of 

 descriptive naturalists — the analytic, or the search for differences — 

 being the proper one, that synthesis should be duly combined with analy- 

 sis, and that general principles should be sought as well as new forms, 

 or so-called "new species" and '-new genera." (4.) It is claimed that 

 nothing is to be gained by giving binomial names to climatic or other 

 form-, in cases where, however considerable the differences between them 

 may be, a complete transition from the one to the other can be traced 

 in specimens from intermediate localities, notwithstanding the plea 

 sometimes urged that their use affords " convenient handles to facts." 



In accordance with such views a partial revision of the species of 

 certain groups is incidentally attempted in Part IV, more especially 

 of the Icteridcc, the raptorial birds, and the genera Pants, Tardus, Pas- 

 serculus, etc. 



Part I. 



The Topographical, Climatic, and Faunal Characteristics of East 



Florida. 



No part of the Florida Peninsula, as is well known, is much ele- 

 vated above the level of the sea, the greater, port ion being extremely 

 low and lame areas swampy. The surface is slightly undulating, but 

 tin; higher ridges randy attain a height of more than lifiy or seventy- 

 five feet, and the highest eminence is less than two hundred. A large 

 part of Northern Florida, including what is usually termed Fa-t and 

 West Florida, is covered with open pine forests, constituting the so- 

 called " pine barrens." These barrens frequently rise into dry knolls, 

 but they likewise embrace considerable tract- that are so low as to be 

 more or less submerged during a portion of the year, especially in wet 



