No. 2389. FAUNA OF THE MARYLAND ARUNDEL— GILMORE. 593 



Berry's conclusion, based alone on the evidence of the floras, that 

 the Patuxent and Kootanie formations are of approximately the 

 same age, as graphically shown in the foregoing diagram, is now fully 

 in accord with the vertebrate evidence as indicating a higher position 

 in the Lower Cretaceous for the Arundel formation than has been 

 previously given it. The only difference between these two lines of 

 evidence is that, whereas "the Patuxent-Arundel floras are essen- 

 tially a unit of early cretaceous age whose affinities all lie with the 

 floras which preceed them," the affinities of the Arundel vertebrate 

 fauna is divided, the Sauropod dinosaurs having close relationships 

 with the preceding fauna and all others apparently having their 

 closest affinities with those faunas which succeeded the Arundel. 



EXPLANATION OF PLATES. 



Plate 110. 



Fig. 1. Tooth of Goniopholis"? affinis Lull. Type. Cat. No. 8452, U.S.N.M. Natural 

 size after Lull. See p. 589. 



Fig. 2. Tooth of Dryptosavrusl medius (Marsh). Type. Cat. No. 4972, U.S.N.M. 

 Natural size. Lateral view. See p. 583. 



Fig. 3. Tooth of Priconodon crassus Marsh. Type. Cat. No. 2135 U.S.N.M. 

 Natural size. Outer, edge, and inner views. After Marsh. See p. 588. 



Fig. 4. Ungual phalanx of the manus of an unidentified dinosaur from the Belly 

 River formation, Upper Cretaceous of the Red Deer River, Alberta, Canada. Cat. 

 No. 5387, Amer. Mus. Nat. Hist. Twice natural size. Lateral view. See p. 586. 



Fig. 5. Ungual phalanx of the manus of Coehtrus? gracilis Marsh. Type. Cat. 

 No. 4973, U.S.N.M. Twice natural size. Lateral view. With the exception of 

 the difference in size, note the close similarity of figures 4 and 5. See p. 585. 



Plate 111. 



Fig. 1. Anterior caudal centrum of Antrodemus valens Leidy. From the Morrison 

 formation of Wyoming. Cat. No. 8367, U.S.N.M. About one-half natural size. 

 Viewed from the left side. See p. 584. 



Fig. 2. Anterior caudal centrum of Dryptosaurus? potens (Lull) from the Arundel 

 formation of Maryland. Type. Cat. No. 3049, U.S.N.M. About one-half natural 

 size. Viewed from the left side. Compare the straight ventral border of this bone 

 with the anterior caudals of Dryptosaurus aqvilunguis, pi. 114, fig. 2. See p. 584. 



Plate 112. 



Fig. 1. Second phalanx digit III, right, of Ornithomimus affinis Gilmore, Cotype. 

 Cat. No. 5703, U.S.N.M. Anterior view. Natural size. See p. 586. 



Fig. 2. Second phalanx digit III, right, of an Ornithomimid dinosaur from the 

 Belly River formation, Upper Cretaceous, Alberta, Canada. Cat. No. 5201, Amer. 

 Mus. Nat. Hist. Anterior view. Natural size. See p. 586. 



Fig. 3. Proximal phalanx of digit II, left Ornithomimus affinis Gilmore, Cotype. 

 Cat. No. 5453, U.S.N.M. Anterior view. Natural size. See p. 586. 



Fig. 4. Proximal phalanx of digit II, left, of an Ornithomimid dinosaur, same as 

 fig. 2. Natural size. See p. 586. 



27177— 21— Proc.N.M.vol.59 38 



