LIASSIC FORMATIONS. 



45 



PI. XVII, the metacarpal of one wing-finger is clearly shown at /' -« That of the other, lying 

 upon the cranium, is more obscure. The thin compact wall of this pneumatic bone has been 

 crushed in upon the wide air-cavity, as with most of the other long bones, so that it looks 

 like two metacarpals. The proximal articular surface of n-m is partly concave and partly 

 convex : the distal articulation is trochlear, moderately concave from side to side at the 

 middle, convex from behind forward, with a depression behind, above the articulation, for 

 securing the olccranoid process of the proximal phalanx. This phalanx (/,- i), in one 

 wing, is bent back upon the fore-arm, crosses the dislocated mandible, and has been 

 pressed upon it, long and hard enough to leave a channel in the right ramus, where part 

 of the phalanx has been removed : its length is 4 inches G lines. 



The second, more slender and longer phalanx 2), is bent at nearly a right angle 

 with the first, and lies below and parallel with the mandible : it is nearly 5 inches in 

 length. The third phalanx 0, 3) is bent upward in front of both lower and upper jaws : 

 4^ inches of its length is preserved in the slab : from the analogy of the better pre- 

 served specimens (PI. XVIII, 3), about I inch 3 lines are wanting from the 

 distal end. 



Of the three unguiculatc digits the characteristic large claws are preserved : one (//) lies 

 above the frontal (11) with the penultimate phalanx ; the other two are between the upper 

 and lower jaws, with some of the slender phalanges : all these parts of the ramus having 

 been dislocated and scattered. 



Parts of the distal ends of the radius and ulna (54', 55')^ the metacarpal of the 

 wing-finger (/' »'•), and the proximal end of its first phalanx of the opposite fore- 



limb, occupy a lower corner of the slab ; carpal bones, one of the accessory styloid ossicles 

 of the forearm, some of the slender metacarpals of the claw-fingers can be made out 

 above these : and there are more obsciu'e indications of vertebrae at that end of the slab, 

 curving toward the cranium. 



All the osseous and dental textures arc black, as if charred by slow combustion of the 

 animal matter. 



DiMORPHODON MACRONYX. PI. XVIII. 



In August, IbGS, I was favoured by the Earl of Enniskillcn, then at Lyme Regis, 

 Dorsetshire, with a list of parts of a Pterodactyle, in a slab of Lias about 20 inches by 

 11 inches, and of otiier [)arts in detached portions of Lias, including the entire tail with its 

 bone-tendons, which his Lordship had observed at Messrs. James and Henry Marder's, 

 the judicious and persevering collectors of the fossils of that rich locality. 



The result of this valnal)le and timely information was the securing for the British 

 ■Museum the entire series of these Pterosaurian fossils. 



