298 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 57 



DESCRIPTION OF PLATE 46 



PAGE 



Proticliiiites scpteinnotatus Owen. (See pi. 47) 278 



Fig. I. (Natural size.) Broad track showing trifid imprint and furrow 

 made by dragging of ventrum or more probably base of 

 caudal furca in the sand. U. S. National Museum, Cata- 

 logue No. 58592. 

 The specimen represented is from locality (220b), Upper Cam- 

 brian, Potsdam sandstone, near Beauharnois, Province of Quebec, 

 Canada. 



