848 SKART— SKELETON 



crown, tail and wings — the last conspicuously barred with white, 

 while neither hens nor young exhibit any striations. On the other 

 hand, neither sex of the latter at any age puts off its striped garb — 

 the mark, it may be pretty safely asserted, of an inferior stage of 

 development. Tlie remaining species of the group, mostly South- 

 American, do not seem here to need particular notice. 



SKAET, see Scarf and Scart (p. 815). 



SKEEL-DUCK, SKEEL-GOOSE, SKEELING and SKELDER 

 (see Shelder), local names for the Sheld -DRAKE, the last also 

 applied to the Oyster-catcher. 



SKELETON, the bony framework of a Bird or other vertebrate 

 animal which, from the ease with which it can be freed from the 

 more perishable soft parts of the body and durably preserved, has 

 long attained a pre-eminent place in anatomical study. This pre- 

 eminence is still further justified not only from the numerosity of 

 the bones composing the skeleton — the very number alone affording 

 great amplitude of differential variability — but because each indi- 

 vidual bone is modelled by its neighbouring soft parts, and notably 

 by the muscles, so that its shape reflects (so to speak) important 

 features of the various organic systems (page 604). Most bones, 

 either in their shape generally, or from the processes, tuberosities, 

 crests or foramina they exhibit, are so characteristic that it is 

 frequently possible to determine not only the Family but even the 

 genus or species of Bird to which they belong. Unfortunately it 

 often happens that the characters selected for taxonomic purposes 

 are those which are the easiest to describe rather than those which 

 are the most important. For convenience of treatment the Skeleton 

 may be regarded as made up of three chief portions — the Head, the 

 Trunk and the Limbs. Frequently a distinction is made between 

 the Axial and the Appendicular Skeleton — the former being 

 restricted to the Vertebral Column and the Cranium proper, while 

 the latter comprises the RiBS, Breastbone (Sternum), Limbs and 

 their arches, the Hyoid apparatus and the Jaws. 



The Vertebral Column has for its chief function the support 

 of the Head and Limbs, as well as the protection of the Spinal 

 Cord, the Vertebrae being its constituent units. These last are 

 distinguished, according to the several regions of the trunk, as 

 Cervical, Dorsal, Sacral or Pelvic, and Caudal, and may be defined 

 as follows : — 



I. Cervical Vertebrse are all those that lie between the skull 

 and the first vertebra which is connected with the sternum by a 

 pair of complete ribs ; but they may be subdivided into 



(a) Cervical Vertebra?, in the strict sense - — either without 

 rudimentary ribs, as the Atlas, or having rudimentary ribs which 

 are fused with the vertebra ; and 



