12 SMITHSONIAN MISCELLANEOUS COLLECTIONS VOL. 80 



Name Horizon Locality 



Punctatumvestigium circuH- Pennsylvanian Kansas City, Mo. 



formis Butts. 



Thenaropus leptodactylus King. . .Coal Measures Westmoreland Co., Pa. 



Thenaropus macnaughtoni Coal Measures Nova Scotia. 



(Matthew). 



Thenaropus ovoidactylus King. . .Coal Measures Westmoreland Co., Pa. 



Thenaropus pachydactylus King. .Coal Measures Westmoreland Co., Pa. 



Thenaropus sphaerodactylus Coal Measures Westmoreland Co., Pa. 



King. 



SYSTEMATIC DESCRIPTION OF GENERA AND SPECIES 



In the systematic description the genera and species are divided 

 into distinct faunas beginning with that of the Coconino formation, 

 those of the Hermit and Supai following successively. Since none 

 of the genera passes over from one formation into the other, it was 

 thought this manner of treatment would be more convenient for 

 reference than any attempt to group related forms. 



Following the policy inaugurated in my first study of Grand Can- 

 yon footprints, only the best preserved and most characteristic speci- 

 mens were selected for description. In most instances the type 

 specimens consist of trackways showing several steps and usually 

 both the right and left sides of the trail. Had it seemed wise to 

 describe all of the various kinds of imprints found, the faunal lists 

 would have been considerably augmented, but after noting the varia- 

 tions found in the imprints in a trackway of a single individual, the 

 more conservative method was adopted. This study has resulted in 

 nearly doubling the known ichnite fauna of the Coconino, has estab- 

 lished an adequate fauna for the Hermit, and has made a beginning 

 in the development of a fauna for the Supai. One of the interesting 

 facts established is that these three faunas are distinct, one from the 

 other. A few of the tracks may be assigned with some assurance to 

 the class in which they belong, but many more remain in doubt, and 

 with our present information, there is little hope of clearing up these 

 enigmas. 



FAUNA OF THE COCONINO SANDSTONE 



Genus DOLICHOPODUS Gilmore 



Dolichopodus Gilmore, Charles W., Smithsonian Misc. Coll., Vol. ~7, No. 9, 

 1926, p. 6. 



Newly discovered material makes possible some slight emendation 

 of the generic characters of this genus, particularly in verifying some 

 points previously in doubt. 



