KANSAS ACADEMY OF SCIEXCE. 



to dewy eve" they were incessantly upon the wing, exhibiting a dash and buoyancy 

 of flight unknown to other birds. In the protection of their eggs and young they ex- 

 hibited unmistakable promptness and valor, swiftly descending along graceful but 

 vigorous curves to a perihelion point in uncomfortable proximity to the face and 

 eyes of the intruding naturalist. 



The birds of the Dakota period were doubtless even more active than the Terns 

 of the present day. The probable presence of teeth in their jaws was an advantage 

 evidently employed with disastrous effect not only to the fishes which constituted 

 their food, but also to their rivals and enemies — the flying reptiles without teeth. 

 The latter were overcome in the conflict, and teeth are no longer a necessity to 

 birds. 



It is hoped that the discovery of our bird-track may stimulate search for other 

 tracks, and that the evidence for the existence of birds in the Lower Cretaceous may 

 not long depend upon a single "footprint upon the sands of [the Dakota] time." 



A GEOLOGICAL SECTION IN WILSON COUNTY, KANSAS. 



BY ROBERT HAY, OF JUNCTION CITY, KANSAS. 



In April, 1885, the writer was called upon to make some investigations for a coal 

 company in the southeast corner of Greenwood county, and after so doing, spent 

 some time east and south down the Fall river valley, nearly across Wilson county. 

 Some observations were afterward made northwest, about Eureka, but as there was 

 a break in the continuity of the explorations, the last are not noticed in this paper. 

 The general result of the connected observations is the construction of a section 

 parallel with the course of Fall river from the town of that name to a few miles east 

 of Neodesha, in Wilson county. The thicknesses of strata in the western part were 

 obtained by actual measurements both with tape-line and instruments of precision) 

 and the others were carefully estimated from comparisons with the elevations of the 

 San Francisco Railway, kindly supplied by Jas. Dun, Esq., the engineer of the com- 

 pany, and from the actual depth to which the strata have been penetrated by wells, 

 as well as by measurements of precipitous bluffs. In one place a certain stratum 

 was suspected to be merely a local intercalation, a substitute for part of another 

 stratum; but as this could not be satisfactorily determined in the time at my dis- 

 posal, the stratum was left in its place in the section till further investigation should 

 support or throw out its claim to be considered as an addition to the general thick- 

 ness of the formations. It does not, however, affect the result to a greater extent 

 than two per cent. 



The principal points which the writer would note in connection with this section 

 are, (a) the evidence as to the average dip, and (b) the indications of disturbance 

 of the strata. From Neodesha to Fall River, a distance of twenty-eight miles, the 

 ascent of the Frisco railroad is 124 feet, but these stations are separated geologically 

 by a vertical distance of 40.5 feet, the former place being situated about on the upper 

 horizon of the Neodesha sandstone, and the latter in a similar position to the Fall 

 River sandstone. This leaves the difference, 280 feet, to be accounted for by the 

 westerly dip, which is therefore about ten feet to the mile. But this average dip, 

 greater than is found in most parts of Kansas, is by no means uniform through the 

 distance surveyed. A carefully measured mile at the western extremity of the sec- 

 tion gave a dip of 45 feet, and in a quarry about two miles east of the town of Fall 

 River the sandstone ledges were inclined to the horizon at an angle of more than ten 

 degrees. 



