THE ENGLISH SPARRO]V 



381 



hinge called the " quadrate " l^one. Neither upper nor lower 

 jaw bear teeth in living birds, but fossil birds are known which 

 bear teeth. One of the most notable features of the skull of 

 birds is the remarkable length of both the upper and lower 



-fiyyat 



Fig. 352. — Bones of the trunk of the pigeon : th.v.l, first and th.r.o, hist 

 vertebra of the tiiorax ; s.ficr, sacrum; cd.v, caudal vertebrie, ending in 

 the tail piece, %>yi].U. The ribs are short on the neck {cv.r) ; on the 

 thorax tfiey consist of two parts, the vertebral (vr.r), and sternal {st.r) 

 ribs, of which the former bears the uncinate process (unc) ; scp, scapula; 

 cor, corocoid ; fur, wishbone or furcula ; acr.cor, process of the corocoid ; 

 gl.cv, place of union of the humerus ; st, sternum, and its keel, car. The 

 pelvis includes : the ilium, il, ischium, is, and pubis, pu.actb, acetabu- 

 lum for reception of the head of the femur; a.fr, for attachment of the 

 ligaments of the femur ; is. for, foramen of ischium ; obt.n, obturator 

 notch. From Parker and Haswell. 



jaws, which are drawn out to constitute the beak. Another 

 feature is the enormous cavity reserved for the eye. 



Surrounding the viscera are five pairs of ribs which connect 

 below with the huge breastbone or sternum, a bone remarkable 

 for its deep keel. This keel serves for the attachment of the 

 breast muscles, by means of which the powerful downward 



