Larid^e.] 



OSTEOLOGIA AVIUM. 



[Rhyncopsinje. 



Rhyncops, Linn. 



Nigra, Linn. 



Cranium. A slight groove above the orbits, and a slight channel over the centre of 

 the head to the vertex, and very deep transverse channel at the base of the nasal 

 bones ; occipital ridge prominent, and terminated by a spine on each side pointing 

 downwards and forwards; post orbital processes perpendicularly flattened, pointing 

 outwards, and slightly bent downwards at the points ; masseter impression large, down 

 the centre of it a slight ridge ; orbital septum with one small foramen. Palatine 

 bones very broad, and sloping gradually downwards, the hinder edge sloped gradually 

 to the interarticular bones, anterior portion gradually diminishing in breadth ; lacrymal 

 bones anchylosed to the frontal, with a foramen through them ; inferior maxillary at 

 the attachment of the masseter muscles much widened. 



Sternum similar to the Sternince. 



Pelvis also similar, but longer in proportion to the size of the bird. 



Wing-bones very long ; ulna much longer than the humerus ; thumb one-third the 

 length of the metacarpus. 



Leg-bones. Metatarsus with a groove down the front ; tibia not prolonged, but 

 having a slight projection in front. 



Measurements, 



Tenths. 



Length of humerus 35 



Length of ulna 44 



Length of metacarpus . . . . 21 1 



Length of femur ...... 15 



Length of tibia 25 



Length of metatarsus 14 J 



Length of sternum ..... 21 



Tenths. 



Breadth of posterior margin of sternum 1 1 J 

 Breadth of anterior margin of sternum 1 2 

 Depth of keel 



Length of head . 

 Breadth of head 

 Length of pelvis 

 Breadth of pelvis 



Skeleton, Plate XII. L. 



Illustrations. 



Sternum, pelvis, palatine bones, 

 metatarsi, Plate XXXVI. fig. 1. 



53 

 14 

 29 



n± 



and 



227 



