156 FIELD COLUMBIAN MuseuM—GEOLOoGyY, VOL. II. 
‘““The above specimens are all from the Upper Cretaceous of Western 
Kansas.”’* 
“ Nyctosaurus, gen., nov.”’ A second genus of American Pterodactyls 
is represented in the Yale Museum by several well-preserved specimens. 
This genus is nearly related to Preranodon, but may be readily distin- 
guished from it by the scapular arch, in which the coracoid is not co ossi- 
fied with the scapula. The latter bone, moreover, has no articulation at 
the distal end, which is comparatively thin and expanded. The type of 
this genus is Preranodon gractlts Marsh, which may now be called /Vycfo- 
saurus gracilis. It wasa Pterodactyl of medium size, measuring about 
eight to ten feet between the tips of the expanded wings. Its locality is 
in the Upper Cretaceous of Western Kansas. ‘The type specimens of all 
the above species are preserved in the Museum of Yale College.” + 
“In the same geological horizon with the gigantic forms (Pterano- 
don beds) the remains of a single small Pterodactyl have been found. 
This animal was more diminutive than the Jurassic species | Dermodactylus 
montanus|, having a spread of wings not more than three or four 
feet. The jaws were proportionally more slender than in the larger Cre- 
taceous species, and no teeth have been found with them. The humerus 
had a small head and an enormous radial crest, which curved downwards. 
The scapula and coracoid were firmly ankylosed. Some of the trunk 
vertebree have very long transverse processes, or ankylosed ribs, curved 
backward. Some dimensions of this specimen are as follows : 
Length of humerus ._---- .-<._- 322 62 
Greatest diameter of head ...-2--- 2-2-4. -.22 20-3 JS Le 
Transverse diameter across radial crest. -..-.- 2... +2. .- Lc eke 30 
Greatest diameter of distal end-..-2.. 22.225 le 16 
Vertical diameter of humeral glenoid cavity ---- -.2__.._./___ 32 13 
Transverse diametér:..-2-2---.. 22. beef as ee 
“This species may be called Preranodon nanus. Its known remains 
were found by Mr. S. W. Williston, in the Middle Cretaceous of Western 
Kansas.” f 
“The name /Vyctosaurus, applied by the writer to this group, appears 
to have been preoccupied, and hence may be replaced by Vyctodactylus. 
The only species known is Vyctodactylus gracilis.” || 
It is seen that but five vertebra are referred to the sacrum of the 
type of WVyctosaurus gractlis ; if this be a real character one would not 
question the distinctness of the species. Inasmuch as Preranodon has 
six vertebree in the sacrum and one or more lumbars or false sacrals, as in 
*Marsh, l. c., p. 509. 
+ Marsh, Amer. Journ. Sci. Dec., 1876, p. 480. 
{ Marsh, Amer. Journ. Sci. April, 1881, p. 343. 
|| Marsh, Amer. Journ. Sci. April, 1881, p. 343, footnote. 
