PELICANlDiE.] OSTEOLOGIA AVIUM. [PLOTINiE. 



Plotus, Linn. 



Novae Hollandiae, Gould. 



Cranium lengthened, without any orbital septum ; space between the upper edges 

 of the orbits rather narrow ; post orbital processes small ; occipital bone with a slight 

 ridge, projecting most at the centre of the upper edge, and terminating below on each 

 edge, with two strong but blunt spines projecting backwards ; the foramen magnum 

 very large; a large, but not very well denned, depression for the masseter muscles. 

 Palatine bones truncate on their hinder angles, with a slight spine in the centre, and 

 gradually tapering forwards ; interarticular bones thin, and rounded. 



Sternum short, broad, with a wide fissure on each side, on the posterior edge ; keel 

 not extending for above two-thirds of its length, anterior edge slightly scolloped out, 

 the point projecting far forwards, lower edge very slightly arched ; a very slight 

 manubrial process ; the lateral edges of the sternum much constricted in the middle. 



Pelvis with the ilium very much expanded for its anterior half before the acetabulum, 

 then much narrowed, the upper surface of the hinder portion having a central rib, and 

 projecting as a ridge over the ischium, and terminated by a spine on each side, the 

 boundaries of the vertebrae plainly visible; ischiadic foramen very large; ischium 

 expanded outwards on its lower edge ; os pubis with the ends projecting downwards. 



Furculum broad, and very much arched backwards, and broad at its upper extremities, 

 afterwards nearly straight, and anchylosed to the point of the sternum. 



Coracoids very long. 



Scapula long, of moderate width, blunt at the ends. 



Wing-bones long ; ulna and metacarpal bones nearly triangular. 



Vertebral column having the upper cervical vertebrae very much elongated. 



Metatarsus short, flattened. 



Measurements. 



Tenths. 



Length of humerus 54 



Length of ulna 50 



Length of metacarpus 27 



Length of femur 23| 



Length of tibia 37 



Length of metatarsus 20 



Length of sternum 25 



Tenths. 



Breadth of posterior margin of sternum 2 1 



Breadth of anterior margin of sternum 1 9| 



Depth of keel . 9 



Length of head 46 



Breadth of head 9 



Length of pelvis 40 



Breadth of pelvis 15 



Graculus, Linn. 



Cristatus, Fab. 

 Cranium similar in shape to Plotus, but with the end of the maxillary bones bent 

 downwards; the tubercle on the upper edge of the occipital bone has a pointed, 

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