OSTEOLOGICAL C ATA LOCI U K. 



PART III. 



Class AVES. 



The system of Classification followed in the present work is 

 mainly that proposed l)y Mr. Henry Seeboh'.n in his ' Classi- 

 fication of Birds,' and further elaborated in his ' Birds of the 

 Japanese Empire ' *. There are some points in this system 

 which I have slightly modified ; but they are of minor ini- 

 j)ortance when compared with the fact that every group of 

 ])irds, as diagnosed by Mr. Seebohm, possesses a combination of 

 definite features, which are characteristic of the group, and of 

 that group alone, be it Order or Suborder. 



Subclass PASSEBIFOBMES. 



A. Young batched in a helpless condition, and requiring to be 

 fed in the nest for many days, Imt not pissing through a 

 complete downy stage. {Cf. Seebohm, Classif. B. p. 1.) 



[N.B. — The late Professor Sundevall raade the condition of the 

 young at birth a primary character for his division of the Class 

 " Aves." His two great " Agmiiia'' were GiimnofKP.dea and Dupii/- 

 pa;des (Av. Teut. pp. 1, 102, 1 58). The naked condition of the 

 young at birth is thus described bj' him : — "A tuft of down, the 

 forerunner of the actual feather, is attached to the tip of the 



* Seebohm, H. Classification of Birds ; an attempt to Diagnose tlie Sub- 

 classes, Orders, Suborders, and some of the Families of existing Birds. 8vo. 

 London : 188'J. Pp. i-xii, 1-52. 



PART III. I- 



