58 TRANSACTIONS OF THE [Nov. 18, 
side of the trough was pointed out by the foreman of the 
work.* 
A curious and interesting feature is the mode of preservation 
of the fossils occurring in this rock. They are mostly cephalo- 
pods and the shells are as well preserved as are those of mol- 
lusks in the Fort Pierre shales. The brilliancy of the nacre is 
retained, the several laminz of the larger shells are distinct and 
in some of the smaller orthoceratites the shell is almost trans- 
lucent. The condition of preservation suggests that the bitu- 
men was introduced at a very early stage of the rock’s history. 
The weathered portions of the rock exhibit broad bands of 
vegetable origin, the possible source of the bitumen so thoroughly 
disseminated.+ 
Prof. Alpheus Hyatt examined the nautiloid forms found 
here and recognized Solenocheilus collectus M. & W., and Meto- 
ceras cavatiformis Hyatt; the former species being represented 
by a huge fragment. Other forms occur, but the specimens are 
too imperfect for identification. Orthoceras is abundantly rep- 
resented, but the forms are not those of the ordinary species and 
may be new; Naticopsis altonensis McCh., Huomphalus sub- 
rugosus, Bellerophon sp. near B. hiuleus, Solenomya sp. and 
Orthis pecosit were obtained. The rock is abundantly fossi- 
liferous, though the number of forms does not appear to be great. 
No fossils were observed in the limestone cut by the railroad 
north from Dougherty, but the succession is so regular that 
there seems to be little room for doubt that those beds belong 
to the Carboniferous, and that they should be put into the Coal 
Measures. This portion of the section, as is shown by the fos- 
sils, is equivalent to the Bend division of the Texas Coal Meas- 
ures described by Prof. Cummins.} 
Southward from Dougherty, the railroad soon enters the Ar- 
buckle mountains and reaches limestone cliffs within two miles 
and a half from the station. For somewhat more than two 
miles further it follows the canon of Wichita river, whose walls 
are limestone bluffs in which the beds dip northwest to almost 
*Mr. C. O. Baxter, President of the Gilson-Asphaltum Company, informs me that 
since my visit a new mine has been opened on the opposite side of the trough, about a 
mile and a half west from this excavation. There the limestone is about 20 feet thick, 
with barely one-fifth of 1 per cent. of silicious matter. The bitumen is from 8 to 10 per 
eent. and of what may be termed the normal consistency. The chemical analyses 
show that this rock is very closely similar to that from Valde Travers and Seyssel. 
The fossil remains in this pit are reported to be different from those in the other. 
+In this connection reference may be made to the fact that petroleum has been 
obtained in moderate quantity at about 40 miles northeast from Dougherty on a con- 
cession belonging to Dr. E.N. Wright. The exploration, however, is not extensive and 
nothing is known respecting the value of the deposit. 
tSecond annual report of the Geological Survey of Texas, 1891, pp. 360-367. Mr. E: 
T. Dumble, State Geologist of Texas, writes me, that prior to my visit, he had been at 
Dougherty and had recognized the equivalence of these rocks with the Bend of Texas: 
