THE PIGEON 



403 



frog. The bones are very light and spongy in texture, and most 

 of them, except those of the tail, forearm, hand, and hind- 



Fig. 293. — The skeleton of a pigeon, seen from the left side. 



c.r.j Fixed cervical rib ; c.r'., free cervical ribs ; cl. t clavicle ; cor., coracoid ; d., 

 dentary ; Mu., Eustachian tube; e.oc, exoccipital \f.r. y fenestral recess;^., 

 femur 'yji'i fibula '.Jr., frontal; hu., humerus; i.f., iliosciatic foramen ; i.o.s., 

 interorbital septum ; il., ilium ; zj., ischium ; lac, lacrymal ; inc. 1-3, metacar- 

 pals ; mt. 1-4, metatarsals; »., nasal; o.f., obturator foramen;^., patella; 

 par., parietal ; ph., 1-4, phalanges;}*/., palatine ; pm. t premaxilla ; p.a.p., 

 postorbital process of frontal ; pi., pterygoid ; pu., pubis ; pyg:, pygostyle ; g., 

 quadrate ; r.c, radial carpal ; ra. } radius ; s.o.5., suborbital bar ; s.oc, supra- 

 occipital ; sa., supra-angular ; sc, scapula ; sg., squamosal ; st., sternum ; st.7\, 

 sternal ribs; //., tibia; u.c, , ulnar carpal; i*.p., uncinate process; uL, ulna; 

 v.cd., caudal vertebra ; v.r., vertebral rib ; x.p., xiphoid process ; zy., zygomatic 

 process of the squamosal ; /,, II., foramina for first two cranial nerves; 1-3, 

 first three cervical vertebrae, 



