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vol. 59 



known below the Upper Cretaceous (Belly River) ; an armored dino- 

 saur, Priconodon crassus, which Lull, correctly recognizes as having 

 its closest affinities with Palaeoscincus of the Upper Cretaceous; a 

 carnivorous dinosaur having a caudal vertebra most nearly resembling 

 the Upper Cretaceous Dryptosaurus from New Jersey; and the smaller 

 Theropod Coelurus? gracilis based on a claw of the fore foot, that 

 except for its much smaller size has its exact counterparts in collec- 

 tions from the Belly River formation. 



Summing up the evidence, such as it is, we have on the one hand 

 in the Arundel the presence of Sauropodous dinosaurs which have 

 been generally considered as not having survived after the close of 

 the Morrison, and on the other hand one family of known Upper 

 Cretaceous occurrence, and at least three other forms which have 

 their closest resemblances with Upper Cretaceous dinosaurs. Imper- 

 fect as it is, the weight of the vertebrate evidence would appear to 

 favor a higher position in the geological scale than has been attributed 

 this fauna in the past. 



In this connection it is of interest to find that this conclusion is 

 more in accord with the paleobotanical evidence, as interpreted by 

 Berry, than the previously accepted correlation of the Arundel with 

 the Morrison. Berry, 33 in comparing the floras of the Arundel and 

 Kootanie of Montana, observes: 



The two floras have a great many elements in common, and upon the basis of the 

 floras alone the conclusion would be reached that the base of the Kootanie was approxi- 

 mately the same age or slightly older than the base of the Patuxent (a formation con- 

 formably underlying the Arundel). When the faunas are considered it develops that 

 the Morrison fauna, which is considered by many paleontologists to be of Jurassic 

 age, is found conformable beneath the beds containing the Kootanie flora, which is of 

 unquestioned Lower Cretaceous age. Along the Atlantic seaboard this is reversed 

 and the bulk of the flora corresponding to that of the Kootanie underlies beds con- 

 taining a large representation of the Morrison fauna, and which also has been con- 

 sidered to be Jurassic age by Marsh and others. 



33 Lower Cretaceous, Maryland Geol. Survey, 1911, pp. 155-156. 



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