12 PROCEEDINGS OF THE BOSTON MEETING 



rant giving it a separate designation. For this division Haworth's term Pleas- 

 anton * seems to liave precedence. 



For the middle member there is no good term, though Henrietta has been used 

 in the general sense here suggested ;t but if this usage is to be adopted, it would 

 seem desirable that the formation be properly defined and some general section of 

 it as typically exposed be given. Since, however, Henrietta was first applied to a 

 distinctive phase of the formation, that displayed in southwestern Missouri, it will 

 probably be found better in the end to adopt a general term for the whole region, 

 retaining the terms now in use, Pawnee, Oswego, Henrietta, Appanoose, and Rac- 

 coon River beds, for local use. This is the more advisable, since, while the beds 

 show certain general characters common to all and are proba!)ly of essentially 

 contemporaneous origin, they really contain the record of deposition in four and 

 perhaps more essentially distinct tliougli minor geological provinces. 



This paper is printed in full in tlie Journal of Geolog}^ vol vi, pages 



577-588. . 



THE PRINCIPAL MISSOURI A.N SECTION 

 BY CHARLES H. KEYES 



The following paper was read by the author: 



TOURMALINE AND TOURMALINE SCHISTS FROM BELCHER HILL, COLORADO 



BY HORACE B. PATTON 



Remarks were made by Vice-President Emerson. The paper is printed 

 in this volume. 



The Society adjourned at 1 o'clock p m for the noon recess, and re- 

 convened at 2 o'clock. The first paper of the afternoon was entitled 



NOTE ON A METHOD OF STREAM CAPTURE 

 BY ALFRED C. LANE 



I do not know whether it was the result of my instruction or of my own miscon- 

 ceptions that I used to conceive of stream capture as culminating in a somewhat 

 sudden diversion of the captured stream, perhaps in time of flood, into the channel 

 of the conquering stream. Such terms as " piracy " carry with them, perhaps unin- 

 tentionally, the thought of violent and sudden action. 



In any case the method of rearrangement of drainage which I shall attempt to 

 describe struck me as a novelty when I first came upon it in operation. In this 

 process the valley of the weaker stream is drained by subsurface drainage until 

 the valley becomes a dry valley, except in times of rain. As soon as the channel 

 is verdure clad, erosion practically ceases and the valley level remains stationary, 

 or may even rise through loam washed down from the side, until some stream 



♦ Kansas University Quarterly, vol. ii, p. 274, 1895. 



fKeyes: Proceedings Iowa Academy of Science, vol. iv, p. 23, and Engineering and Mining 

 Journal, February 26, 1898, p. 2o4. 



