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 insectwing were found in siIn 6

2. Close up view of the fossiliferous ledge indicated by the cross in fig. I. The projectingledgeextending tothe 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 froniia 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. Foundand 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

infig. 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 thelowerleft 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, Laoporusnoblei Lull. No. 11,494, U.S. N. M. Showingtheespeci- ally longsecond and third digits of the manus.

X

3 18

NO. 3

GRAND CANYON

FOSSIL

FOOTPRINTS GILMORE

_"JJ Plate 5

Figs, i and 2. Barypodus tridactylus, new species Type. No. 11,502, U. S. N. M. Showing trackway. Fig. i, upper or positive slab;

fig. 2, loweror negative slab.

X

2.64 20 Plate 6

Barypodus mctsacri, new species. Type. No. 11,505, U. S. N. M. Irregu-

lar trackway.

X

3 21

Plate₇

Baropus coconinoensis, new species. Type. No. 11,514, U. S. N. M. Left

side of trackway. X, 3.2 24

Plate 8

Agostopiis mcdius, new species. Type. No. 11.509, U. S. N. M. Track-

v^'ay.

X

346 •, 27

Plate ₉

Amblyopus pachypodus,

new

genus and species. Type. No. 11,511, U. S. N. M. Trackway; outer rows of impressions made by forefeet,inner, those ofthe hindfeet.

X

^4-57 29

Plate 10

Fig. I. Triavcstigia niningcri, new genus and species. Type. No. 11,510, U. S. N. M. Tail dragclearly shown between the parallel rows

of tracks on the left side.

X

1.3 33

2. Octopodichnusdidactylus,new genus-dud species. Type. No. 11,501,

U. S. N. M.

X17

31

Plate ii

Unisulcus siniiostis, new species. Type. No. 11,497, U. S. N. M. Three

trails crossing slab.

X

² 35

Plate 12

Batrachichnusdelicatula (Lull) No. 11,519, U. S. N. M. Large slab whose surface is thickly covered with minute tracks.

X

^4-5 36

Plate 13

Batrachichnus obscurus, new ^species. Type. No. 11,529, U. S. N. M.

Trail showing where belly dragged in the mud. Plant impres- sions. Large tracks those ofHylopus hcniiitcnsis.

X

^{-2.7 40}

Plate 14

Dromillopus parvus, new species. Type. No. 11,537, U.S.N.M. Track-

way

withtail dragbetween. Tracks on ^leftside belong to some

five-toed creature. .71 over natural size 42

yS

SMITHSONIAN MISGELLANEUUS COLLECTIONS

^VOL.

8o

Plate 15

Hylopus hcntiitcnsis, new species. Type. No. 11,517. U. S. N. M. Track- wa}' showing variation in successive impressions.

X

^{^} 46

Plate 16

Hyloidichnus bifurcatus, new genus and species. Type. No. 11.518, U. S.

N. M. Trackway on the positiveslab.

X

^{2 S^}

Plate 17

Fig. I. ParnbaropHS coloradcnsis (Lull) No. 11,598, U. S. N. M. Left side of trackway. Photographed from the cast of the original

specimciL

X

3 54

2. Cursipcs sp. Trackway from the Hermit shale. No. 11,521,

U. S. N. M.

X

^{1.9 ^3}

3. Unidentified track. No. 11,530, U. S. N. M.

From

the Hermit

shale. About natural size 65

Plate 18

Unidentified track. No. 11,528, U. S. N. M. The largest trackyet found

in the Hermit formation.

X

^1-85 64

Plate 19

Fig. I. Collcttflsannis pcntadactylus, new species. Type. No. 11,527, II. S. N. M. Trackway showing

how

the

mud

flowed into the

tracks as the foot was withdrawn.

X

² 60

2. Stenichnns yakiensis, new genus and species. Type. No. 11,533,

U. S. N. M. Trackway.

X

^{2 66}

Plate 20

Anomalopus sturdcz'anti, new genus and species. Type. No. 11,517, U. S. N. M. Trackway on slab.

X

^{2.5 68}

Plate ²¹

Tridentii hints supaiciisls, new genus and species. Type. No. 11,534, U. S. N. M. Trackway on slab.

X

^{2.2 70}

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80, NO.3,PL. 1

Locality of fossil footprints, Grand Canyon.

(For explanation, see page ₇₆₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^{VOL. 80,NO. 3,PL. 2}

I. Looking up Yaki Trail.

2 and 3. Fossil footprints from the Grand Canyon.

(Kor explanation, see page 76)

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^VOL. 80, NO.3, PL.

3

^ (

'i*>

Fossil footprints fromtheGrand Canyon.

(.I'or explanatiun. see page 76)

L

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80, NO.3, PL.4

.1*

1 2

Fossil footprints from theGrandCanyon.

(For explanation, see page ₇₆₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80,NO. 3,PL. 5

Fossil footprints fromtheGrand Canyon.

(.For explanation, see page 77)

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 80,NO. 3, PL.

6

SMITHSONIAN MISCELLANEOUS COLLECTiONS VOL. 80, NO.3,PL.7

''^''^..

Fiissil footprints fromtheGrand Canyon.

(For explanation, see page 77)

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80, NO.3,PL. 8

Fossil footprints fromtheGrand Canyon.

(For explanation, see page "jy^

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80, NO.3, PL. 9

Fossil footprints fromtheGrand Canyon.

(For explanation, see page ₇₇₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80, NO.3, PL. 10

Fossil footprints fromtheGrand Canyon.

(For explanation, see page 7r)

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80,NO.3, PL.11

Fossil footprints fromtheGrand Canyon.

(.For explanation, see page 77)

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^{VOL.80, NO.3, PL. 12}

Fossil footprints fromtheGrand Canyon.

(For ex])lanation. see page ₇₇₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^{VOL.80, NO. 3,PL. 13}

Fossil footprints fromtheGrand Canyon.

(For explanation, see page 77)

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^VOL.80, NO. 3 PL. 14

< ^{\''- <}

Fossilfootprints fromtheGrand Canyon.

(Forexplanation, see page /7)

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^{VOL. 80, NO.3,PL. 15}

Fossil footprints fromthe GrandCanyon.

(For explanation, see page 78)

SMITHSONIANMISCELLANEOUS COLLECTIONS VOL. _80, NO.3.PL. 16

Fossil footprintsfrom theGrand Canyon.

(For explanation, see page ₇₈₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL._80, NO.3,PL. 17

1 2

Fossil footprints fromthe Grand Canyon.

(For explanation, see page 78)

SMITHSONIAN MISCELLANEOUS COLLECTIONS ^VOL.80, NO 3, PL. If

Fossil footprintsfrom theGrand Canyon.

(l^'orexplanation, see page ₇₈₎

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. _80,NO. 3,PL. 19

1 2

Fossil footprintsfrom theGrand Canyon.

(For explanation, see page 78)

SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL.80,NO. 3,PL.20

Fossil footprints fromtheGrand Canyon.

(For explanation, seepage 78)