864 



HISTORICAL GEOLOGY. 



horridus of Huxley occurs in the Upper Cretaceous, and Megcdosaurus Bredai 

 of Seeley at the top of the Cretaceous in the Maestricht beds. Mosasaurids 

 make their hrst appearance after the Neocomian, as in America ; a Liodon 

 occurring in the Upper Chalk, and Mosasaurus Camperi Meyer (Fig. 14G6), 

 in the Maestricht beds, and also at Lewes, England. 



1466. 



Mosasaurus Camperi (x ^s)- » 



At Gosau in the northeastern Alps, Austria, remains of the horn-cores 

 of Ceratopsids have been found in beds of the Upper Greensand, and described 

 under the name Struthiosaurus. 



3. Birds. — Imperfect remains of two species of Enaliornis Seeley have 

 been obtained from the Cambridge Greensand ; and Professor Seeley observes 

 that they may be related to the Hesperornis of Kansas. A species of Palceornis 

 occurs in the Wealden. 



. 4. Mammals. — Only one species had been reported up to 1894. It is 

 referred to the Jurassic Marsupial genus Plagiaidax. The only specimen 

 is a molar tooth from the Wealden of Hastings (S. Woodward, 1891). 



Local Subdivisions and their Characteristic Fossils. 

 1. Lower Cretaceous. 



A. Great Britain. — 1. The Wealden. (a) The Hastings sand and clays, or Lower 

 Neocomian, which have afforded, besides plant remains and fresh-water shells, the bones 

 of many Saurians. 



(6) The Weald clay or Middle Neocomian (400'-1000'), containing, at a level about 

 100' from its top, the Paludina limestone, sometimes called Sussex marble, consisting 

 chiefly of fresh- water shells of Pa?r«diJia ^icyion/m — a marble "renowned in the annals 

 of church architecture." In addition to fresh-water shells, and fish remains, there are 

 remains also of Reptiles ; and on the Isle of Wight occur Exogyra sinuata and an Ostrea. 



The Lower Greensand, 250'-450', overlies the Wealden in southern England, but over- 

 laps northward the Upper Oolytic beds. Contains Ammonites {Hoplites) Desliayesi, 



