CRETACEOUS FORMATIONS. 



19 



4to, 1851, e.g., is 2 inches 2 lines; that of the wing-bone, figured in Tab. IV, figs. 

 1 — 3 of the present Monograph, is 3 inches. The transverse diameter of the distal 

 end of the humerus of Pterodactylus grandis, Cuv., the largest species hitherto 

 obtained from the Lithographic Slates of Germany, is 1 inch 3 lines ; neither the 

 radius, ulna, nor metacarpal of the wing-bone of the same species presents a diameter 

 of its largest end equalling 1 inch.* 



The articular end of the long wing-bone (Tab. IV, figs. 1 — 3), being most pro- 

 bably that of an antibrachial bone, and the total length of the bone, whether radius 

 or ulna, being, according to proportions of either of these bones in Pterodactylus 

 sueviais, 1 6 inches, the following would be the length of the other long bones of the wing 

 in the large Pterodactyle to which the above-cited specimen belonged, according to the 

 proportions which those bones bear to the radius or ulna in Pterodactylus suevicus : 



Humerus . 



. 



Radius 





Metacarpus of wing-finger 



First phalanx of 



do. 



Second do. 



do. 



Third do. 



do. 



Fourth do. 



do. 



Total length of long-bones of one wing 



l^f 



lu. 



Lines 















4 









8 







2 



3 









9 









5 









1 







10 



Supposing the breadth of the Pterodactyle between the two shoulder-joints to be 

 8 inches, and allowing 2 inches for the carpus and the cartilages of the joints of the 

 different bones, in each wing, we may then calculate that a large Pterodactylus Sedywickii 

 would be upborne on an expanse of wings of not less than 22 feet from tip to tip. 



I look forward with confidence to future acquisitions of remains of the truly 

 gigantic Pterodactyles of the cretaceous periods, more especially from the Green- 

 sand locality, near Cambridge, as a means of throwing more light on the peculiar 

 osteology of the extinct flying reptiles. 



For the opportunities at present afforded me, I have to express most grateful 

 acknowledgments to my old and much esteemed friend the Rev. Professor Sedgwick, 

 F.R.S. ; to the acute and active curator of the Woodwardian Museum, Mr. Lucas 

 Barrett, F.G.S. ; to James Carter, Esq., M.R.C.S., Cambridge ; to T. W. Beddome, 

 Esq., of Trinity College, Cambridge; and to the Rev. G. D. Liveing, M.A., of St. John's 

 College, Cambridge, to whom I am indebted for the lower jaw of Pterodactylus 

 Sedgwickii (Tab. I, figs. 2, a, b, c, d). 



* These admeasurements are derived from the excellent figures of a recently acquired specimen, well 

 described by Professor Andreas Wagnisb of Munich, in the " Abhaudlungen der Kais. Bayer. Akademie 

 der Wissenschaft," Band iii, p. 663, taf. xix. 



[1857 volume.] 



