Xiv NORTH AMERICAN BIRDS. 



the true relations of the members embraced under those heads. Enough 

 has also been adduced to enable us to group many forms into families and 

 somewhat more comprehensive groups, definable by osteological and other 

 characters. Such are the Charadrimorphte, Cecomorphse, Alectoromorphae, 

 rteroclomorphae, Peristeromorphie, Coracomorphte, Cypselomorphse, Celeo- 

 morphse, Aetomorphie, and several others. But it is very doubtful whether 

 the true clew to the aflinities of the groups thus determined has been found 

 in the relations of the vomer and contiguous bones. The families, too, have 

 been probably, in a number of cases, especially for the passerine birds, too 

 much circumscribed. The progress of systematic ornithology, however, has 

 been so rapid within the last few years, that we may be allowed to hope that 

 in a second edition of this work the means may be furnished for a strictly 

 scientific classification and sequence of the families. (T. N. G.) 



A primary division of recent birds may be made by separation of the 

 (a) Batitcc, or struthious birds and their allies, — in which the sternum has 

 no keel, is developed from lateral paired centres of ossification, and in which 

 there are numerous other structural peculiarities of high taxonomic import, — 

 from the (h) Carinatcc, including all remaining birds of the present geologic 

 epoch. Other primary divisions, such as that into Altrices and Prcccoces 

 of Bonaparte, or the corresponding yet somewhat modified and improved 

 Fs'Uojjaedes and Ptilopacdcs of Sundevall, are open to the serious objections 

 that they ignore tlie profound distinctions between struthious and other 

 birds, require too numerous exceptions, cannot be primarily determined by 

 examination of adult specimens, and are based upon physiological considera- 

 tions not necessarily co-ordinate with actual physical structure. 



In tlie following sclieme, without attemj)ting to indicate positive taxo- 

 nomic rank, and without committing myself finally, I present a number 

 of higher groups into which Carinate birds may be divided, capable of ap- 

 proximately exact definition, and apparently of approximately equivalent 

 taxonomic value. Points of the arrangement are freely drawn from the 

 writings of various authors, as will be perceived by those competent to judge 

 without special references. I am particularly indebted, however, to the 

 late admirable and highly important work of Professor Sundevall,^ from 

 which very many characters are directly borrowed. The arrangement, in 

 effect, is a modification of that adopted by me in the " Key to North Ameri- 

 can Birds," upon considerations similar to those herewith implied. The 

 main points of difference are non-recognition of three leading grouj^s of 

 aerial, terrestrial, and natatorial birds, — groups without morphological Ijasis, 

 resting simply upon teleological modification ; a general depreciation of the 

 taxonomic value of the several groups, conformably with the considerations 

 presented in the preceding pages of this work ; abolishing of the group 

 Grallatores ; and recognition of a primary group Sjjhenisci.^ 



' Methodinaturalis avium disjmnendar urn tcntamen. Stockholm, 1872-73. 



^ This group is insusceptible of definition. The wading birds, as usually allocated, do not 



