416 MK. K. W. HOOLEY. OK THE [June IC|I3, 



- set with great regularity in the alveolar border, showing little variation 

 in size, interlocking. Six tree dorsal vertebrae. Humeral articulation 

 with the radius a well-developed trochlea, with the ulna a highly- 

 specialized hinge-joint dorsal to the radius. Shaft of radius very 

 attenuated. Small metacarpals articulating with the carpus dorsally to 

 the wing-inetacarpal. Keck and head ot the femur terminal, shaft 

 straight. 



II. Sub- Order : Pterodactyloidea. 



Half the area of the skull encased in bone, all fossas moderately large. 

 Nasal and preorbital vacuities confluent. Convex bird-like occiput. 



Family: Pterodactylidae. 



Skull bird-like, with a long or short muzzle. Dorsal vertebra? not 

 fused into a notarium. Sacral ribs tree (Pt. antiquus) or anchylosed 

 (I't. suevictts). Tail short. Sternum semi-elliptical, with an anterior 

 spine. Scapula and coracoid separate. Humeral crest wing-like, with 

 the superior border convex. Wing-metacarpal greater than half the 

 length of the ulna. Pre-pubic bones fan-shaped. 

 Genus: Pterodactykcs. 



Sub-Family: Ptenodraconinaj. 



Skull short. Preorbital and nasal vacuities separated. 

 Genus : Ptenodracon. 



in. Sub-Order: Khamphorhynchoidea. 



Skull nearly encased in bone, all fossae considerably reduced. Nasal 

 and preorbital vacuities separated. Occiput flat. 



Family: Rhamphor hynchidae. 



Skull without a supraoccipital crest. Jaws toothed. Dorsal vertebras 

 not fused into a notarium. Sacrum a shield-shaped anchylosed mass, with 

 loramina. Loug-tailed. Sternum rhomboidal, anterior spine, no keel. 

 Deltoid crest of humerus constricted medially. Wing-metacarpal less 

 than half the length of the ulna. Pre-pubic bones band-like and curved^ 



Genera : Dort/gnathus. | Rhamphocephalus. 



Campylognathus. \ Bhamphorhynchus. 



Family: Ornithostomatidae. 



Skull with prominent supra-occipital crest. Jaws edentulous. Short- 

 tailed. Scapula articulating with the notarium. Wing-metacarpal longer 

 than the ulna. 



Genus: Orniihostoma (Pteranodon) . 



Sub-Family: Nyctosaurinse. 



No supra-occipital crest to skull. Edentulous. Tail short. Scapula. 

 not articulating with the early dorsal vertebra?. 

 Genus: Nyctosaurus (Nyctodactylus). 

 No antorbital vacuity. 



Family: Ornitkoeheiridas. 



Longitudinal ridge on the palate. 



Sub-Family: Ornithocheirinae. 



Teeth prolonged anterior to the palate. 

 Genus: Omithocheirus. 



