During the Cretaceous Period 213 



(2) That the Wealden rivers continued in existence, 

 although probably in much diminished volume, during the 

 accumulation of most of the succeeding Neocomian strata. 



Meyer however considers that occasional marine in- 

 trusions took place, and so gave rise to the deposits with 

 Ostraea, Mytilus and similar marine organisms. He further 

 states that "the higher beds of the Wealden are not only 

 extremely uniform in character, proving to some extent 

 their deep-water origin, but also contain freshwater fossils 

 up to their very junction with the Neocomian strata. Speak- 

 ing also of the passage beds and of the Lower Neocomian, 

 he says, quoting Fitton, that these include "a large quantity 

 of a kind of gravel, containing numerous fragments of fish 

 bones. It is just such an accumulation of sediment as would 

 result from the dispersion of shore deposits over the floor 

 of a moderately deep lake." He also regards the "Pun- 

 field" formation of the Isle of Wight as Upper Wealden, 

 and adds: "The occurrence of a Spanish fauna at Punfield 

 proves, if it proves anything, that the Neocomian (Lower 

 Greensand) series of the southeast of England and of 

 Eastern Spain are, in point of age, equivalent deposits." 



The writer is compelled also to take an exactly opposite 

 view from A. S. Woodward (756:69) when he writes: 

 "The Wealden estuary seems to have been the last refuge 

 of the Jurassic marine fish fauna in this part of the world." 

 All exact evidence shows that such Wealden fishes as 

 Hybodus, Acrodus, Aster acanthus, Neorhombolepis, Coel- 

 odus, and Belonostomus, were either once freshwater or 

 derivative marine descendants therefrom, that reached the 

 sea during Jurassic times. For previous to that time no 

 sure commingling of marine invertebrate remains, with 

 fishes that lived alongside them, is known since early 

 Permian time onward, while up to this time Hybodus and 

 Acrodus occur occasionally still in freshwater relation. 



Resembling the Wealden of England, and probably 

 continuous in time, as they are in facies and organic remains, 

 beds occur over a considerable part of North Germany that 

 Geikie (/rH: 1203) summarizes as follows: "Below the 

 Hils-thon in Westphalia, the Harz, and Hanover, the lower 

 parts of the true marine Neocomian series are replaced by 



