THE TKEPAEATION OF THE EARTH FOR MAN's ABODE. 93" 



it is made ii]) are the same in both cases, and one, the- 

 Globigerlna bulloides, is abundant in both the Cretaceous beds 

 and the Atlantic ooze of the present day. 



The fauna of the (Cetaceous rocks is noteworthy as well 

 for what it lacks as for Avhat it iu eludes. One of its lacimce 

 is the absence of mammalian remains in the European area, 

 with the exception of a species ascribed to the genus 

 Plagimdax found at Hastings. Fishes of the highest type, 

 the Teleostei, now make their appearance, and one genus,, 

 the Be7^yx, is not uncommon in the chalk of Surrey and. 

 Sussex. Of the Reptilia, the great Jurassic deinosaurs, 

 although in some abundance still, die out with the 

 Cretaceous epoch, and the same may be said of the 

 pterosaurs. The Cretaceous reptiles have left some 

 remarkable examples for our instruction. Amongst these 

 are the gigantic three-toed Ifjnanodon MantelU of Sussex and 

 Kent, and the still larger Ignanodon Bernissartensis of Belgium,, 

 which have been made well known by our museums ; and 

 the pterodactyles of the Cambridge greensand. But it is to 

 the rocks of the Western States of North America that we 

 owe the greatest exposition of the reptilian forms of the 

 Cretaceous epoch. From these rocks have been obtained 

 many species of deinosaurs, pterosaurs, crocodiles, marine 

 saurians, turtles, and no less than fifty species of veritable 

 sea-serpents, of which the enormously long Mososaurus is 

 best known. These dominating monsters of the Cretaceous 

 seas were some as much as 75 feet long. 



Although birds do not live under conditions favourable for 

 the preservation of their bones, some remarkable species 

 have been entombed in Cretaceous rocks, chiefly in North 

 America. One group, Odontornithes, was toothed, and in 

 the genus Hesperornis the teeth Avere in a common alveolar 

 groove as in the reptilian Icldhyosaurus. Thus some of the 

 birds of the Cretaceous epoch had affinities with the then 

 dying out reptihan groups of deinosaurs and pterodactyles. 

 In America, too, in the Cretaceous rocks of Dakota and 

 Wyoming, a large assemblage of mammalian remains have 

 been discovered. These have been placed by Professor Marsh 

 in sixteen genera, but all are of the lowest orders of 

 Mammalia and allied to the Jurassic forms of the same 

 class. 



A very important advance in plant-life marks the 

 Cretaceous ej)och, for in its rocks are the remains, often 

 beautifully preserved, of the earliest known angiosperms- 



