Parr Il. Sxcr. iii] | CRETACEOUS. 80 
among some of the eastern ranges of the Rocky Mountains (Colorado; 
Black Hills, Dakotah; Wind River Mountains; Uinta Mountains; 
Wahsatch range, &.), as well as in the Sierra Nevada and other 
localities on the western side of the watershed. They have been recog- 
nized also far to the north beyond the great region of Azoic and Paleozoic 
rocks in the arctic portion of the continent. They consist of limestones 
and marls, which appear seldom to exceed a few hundred feet in thick- 
ness. The fossils include species of Pentacrinus, Monotis, Trigonia, 
Lima, Ammonites, and Belemnites. But recent discoveries by Professor 
Marsh of Yale College have brought to light from the upper Jurassic 
strata of Colorado a remarkable series of reptilian forms which have 
_ given a wholly new interest and importance to the Jurassic rocks of 
America. Among remains of fish (Ceratodus), tortoises, pterodactyls, and 
crocodilians, he has recognized the bones of carnivorous and herbivorous 
deinosaurs. One of these, the Ailantosaurus, has already been referred to. 
Other forms are Morosaurus, Apatosaurus, Creosaurus, and Laosaurus, the 
latter having more ostrich-like affinities. With this rich and striking 
reptilian fauna are associated the remains of some small marsupials 
(Dryolestes priscus, Stylacodon gracilis). 
Asia.—In India the upper part of the enormous Gondwana system is 
possibly referable to the Jurassic period. In Cutch, however, a marine 
series of strata occurs containing a representation of the European 
_ Jurassic system from the Inferior Oolite up to the Portland inclusive. 
These rocks attain a thickness of 6300 feet, of which the lower half is 
chiefly marine and the upper mainly fresh-water. Among the zones 
recognized by Stoliczka were those of Ammonites macrocephalus, A. anceps, 
and A. athleta of the Kellaways (Callovian) group; A. Lamberti, A. 
cordatus, A. transversarius of the Oxford clay; A. tenuilobatus of the 
Kimmeridge.! 
Australasia.—The existence of Jurassic rocks in Queensland and 
Western Australia has been demonstrated by the discovery of recognizable 
Jurassic species and others closely allied to known Jurassic forms.? Traces 
of the same system have been found in New Caiedonia and the northern 
end of New Guinea. In Otago, New Zealand, the Putakaka formation 
of Hutton, estimated to be between 9000 and 10,000 feet thick, is referred 
by him to the middle or lower Jurassic period. lt has yielded a few 
fossils (Pholadomya, Astarte, Ammonites). 
- Section III.—Cretaceous. 
The next great series of geological formations is termed the Cre- 
taceous system, from the fact that in north-western Europe one of its 
most important members is a thick band of white chalk (creta). It 
presents very considerable lithological and paleontological differ- 
ences as it is traced over the world. In particular, the white chalk 
-whence its name was taken is almost wholly confined to the Anglo- 
Parisian basin where the system was first studied. Probably no 
contemporaneous group of rocks presents more remarkable local 
1 Medlicott & Blanford’s Geology of India, p. 253. 
2 Moore, Q. J. Geol. Soc. xxvi. 261. W. B. Clarke, Op. cit. xxiii. 7. 
3 YF 
