76 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 8o 



EXPLANATION OF PLATES 

 Plate i 



PAGE 



Fig. I. General view of fossil footprint locality at head of Hermit Gorge. 

 Most of the specimens of fossil tracks and plants from the 

 Hermit shale were collected from the slope above the massive 

 sandstones in the middle foreground. The disconformable Her- 

 mit-Supai contact is plainly indicated on the left side of the 

 photograph. The cross indicates the level where footprints, 



plants, and insect wing were found in si In 6 



2. Close up view of the fossiliferous ledge indicated by the cross in 

 fig. I. The projecting ledge extending to the right from the base 

 of the cedar tree, which is estimated to be 30 feet above the 

 Hermit-Supai contact, contained footprints, plants, and insect 

 impressions. 



Plate 2 



Fig. I. Looking up Yaki trail fronii a point two miles down from the top 

 of the rim, where the trail cuts through a massive sandstone in 

 the middle Supai formation on the east side of O'Neill Butte. 

 Numerous tracks and trails occur in the upper light-colored 

 sandstone seen in the right of the picture 8 



2. Casts of footprint impressions (probably Tridcntichnus sp.) in 



Supai sandstone. These were the first tracks to be found in situ 

 on the Yaki Trail. Found and photographed by Dr. J. C. Mer- 

 riam. These occur at the base of the heavy, darker colored 

 sandstone shown at the right but further down the trail than 

 in fig. I 8 



3. Undescribed trackway on a large block of sandstone from the 



debris blasted out of the upper light colored sandstone (shown 



in fig. I ) in building the Yaki Trail 8 



Plate 3 



Naiwpus iiiaxinius. new species. Type. No. 11,506, U. S. N. M. Showing 

 an irregular trackway. Note the scratches made by a slipping 

 hindfoot on the lower left hand side. X 4.3 iS 



Plate 4 



Fig. I. Nanopus mcrriatni Gilmore. No. 11,516, U. S. N. M. Trackway 

 from lower part of track-bearing horizon in the Coconino 



sandstone. X ^-77 15 



2, Laoporus noblei Lull. No. 11,494, U. S. N. M. Showing the especi- 

 ally long second and third digits of the manus. X 3 18 



