Tf xn PEOOEEDINGS Or THE 



The present paper is one of a series in hand, in which the writer 

 has endeavoured to work out thoroughly the facial characters of cer- 

 tain types of birds, in harmony with the view given by Professor 

 Huxley in his well-known paper " On the Classification of Birds " 

 (Proc. Zool. Soc. April 11, 1867). 



His own mode of research is much more like that followed 

 by the distinguished author of that paper than that pursued 

 by ornithologists proper. Without undervaluing their excel- 

 lent labours, yet there are many things which are seen first and 

 first understood by the embryologist, and not by the zoologist as 

 such. Professor Huxley, in the paper just referred to, separated the 

 forms now under consideration into his group " Coleomorphse," 

 aud gives (p. 467) a very valuable summary of their characters. 

 It was sought in that paper to bring into more or less zoological 

 contiguity such birds as have a similar structure of the facial and, 

 especially, of the palatal bones. The group-terms " Schizogna- 

 thae " (p. 426), " DromseognathEe " (p. 425), &c. are very important, 

 although some of them are of very wide application. 



It was the first thought of the author of this paper that the 

 Woodpeckers would easily find a place amongst the non-passerine 

 aerial birds ; but examination of their palatal structures soon dis- 

 pelled this opinion. They are more allied to the " Passeringe " 

 than most of the Zygodactyles ; but it is to the embryos of that 

 type, and not to the adult, that they are related. The " Pas- 

 serinse " themselves are well termed "^githognathous " (p. 450). 

 This huge group is in hand at present. Large materials have 

 been added to the stores of the writer by Osbert Salvin, Esq., 

 who also has assisted greatly in the matter of the Picidee. He 

 is also indebted to Dr. Murie, Mr. D. Bartlett, and Mr. W. J. 

 Williams. 



Most of the non-passerine birds that seem to come nearest to 

 the Woodpeckers have a very solid palate ; they are " Desmogna- 

 thous;" others, as the Humming-birds and Goatsuckers {Gapri- 

 mulgtis'), are " Schizognathous ; " whilst the Swift {Cypselus) is as 

 perfectly "^Egithognathous " as the Swallows. But the Wood- 

 peckers retain that non-coalesced condition of the palatal struc- 

 tures which we see in the Lizards, very unlike that great fusion 

 of parts towards the mid line which occurs in most of the higher 

 birds. They have also an unusually arrested condition of the pa- 

 latal part of the upper jaw-bone (maxillary), which is characteristic 

 of the Lizard, and unlike the bird-class generally — and bones super- 



