132 CRETACEOUS PALEONTOLOGY. 



Formation. Restricted. Extraterritorial. 



Cliffwood, 40% 49% 



Merchantville, 32% 42% 



Woodbury, 33% 45% 



Marshalltown 23% 60% 



Wenonah, 23% 62% 



Mt. Laurel-Navesink, 48% 42% 



Red Bank 9% 69% 



Tinton, 21% 60% 



Accompanying this larger percentage of species which are 

 restricted to this fauna in New Jersey, the above table shows 

 further that there is a decided reduction in the percentage of 

 species which are extra-territorial in their distribution, or in 

 those which occur also in the Ripley faunas of the Gulf border 

 region, only 42 per cent, being recognized. These two facts, 

 when taken together, suggest that there was an immigration of 

 species into the region from some other direction than the south. 



A third peculiarity of this fauna is the large number of gastro- 

 pods present, as compared with the other faunas in the series, a 

 fact which is shown clearly in the following table recording the 

 number of species of Pelecypods and Gastropods in the several 

 faunas. 



Pelecypoda. Gastropoda. 



Cliffwood, 33 8 



Merchantville, 62 29 



Woodbury, 65 23 



Marshalltown, 35 6 



Wenonah, 59 17 



Mt. Laurel-Navesink, 56 46 



Red Bank, 38 4 



Tinton, 25 5 



It is seen from this that in the Mount Laurel-Navesink fauna 

 a nearly equal number of Pelecypods and Gastropods are present, 

 while the Gastropods do not exceed 50 per cent, of the Pelecypods 

 in any other fauna of the series.^ In the Red Bank and Tinton 



' If the undetermined species were included in this estimate the total num- 

 ber of gastropod species would more than equal the number of pelecypods. 

 Also, if these undetermined forms were included the percentage of restricted 

 species would be materially increased, and the percentage of extraterritorial 

 one reduced. 



