﻿OOLITIC FORMATIONS. 



11 



yet had the opportunity of studying a Pterosaurian carpus or tarsus in so well-preserved 

 and undisturbed a condition as would enable me, with certainty, to determine the 

 homologies of its constituent bones. 



§ 4. Pterosattria of the Great Oolite. 

 A. — Pterodactylus Kiddii, Owen (Plate I, fig. 17). 



The first phalanx of the wing-finger (fig. 17), referable to this species is somewhat 

 stouter, but about one eighth shorter, than that bone in the Pterodactylus suevicus, 

 Quensted, 1 from the Lithographic Slate of Wirtemberg. It indicates a species with a 

 more powerful, though, perhaps, less elongate, wing. The groove for the flexor tendon 

 of the fourth digit, bounded by the prominent thenal extensions of the two articular 

 grooves, is well marked. The extensor process (ib., c) has a relatively longer basis than 

 in the Kimmeridge specimens. A rough groove or linear depression beginning about an 

 inch beyond the proximal articulation, and extending as far down the fore or thenal 

 surface of the shaft of the bone, indicates the extensive attachment or insertion of that 

 tendon. The shaft is subtriedral, the anconal side being the broadest; it becomes 

 flattened towards the distal end, which expands unequally towards the ulnar side, and 

 affords an oblong, moderately developed, concavo-convex surface for the second phalanx 

 of the wing-finger. 



This bone, from the Stonesfield Oolite, is slightly crushed. 



B. — Pterodactylus Duncani, Owen (Plate I, fig. 18). 



The first phalanx of the wing-finger, referred to the above species, is of the left wing, 

 and is imbedded with the anconal surface exposed in a slab of Stonesfield Slate. 



It is from a larger Pterodactyle than the preceding. The extensor process is thicker, 

 but springs from a less extended base, relatively to the length of the bone. 



C. — Pterodactylus Aclandi, Owen (Plate I, fig. 19). 



This species is represented by a still larger specimen of the characteristic wing-bone 

 (fig. 19) in Pterosauria. The olecranoid process ( c ) is shorter in proportion to the breadth 



1 " Ueber Pterodactylus suevicus" 4to, Tubingen, 1855. 



