Local Hydrography 67 



A. LAND-AND-WATER STUDIES 



Study 1 

 LOCAL HYDROGRAPHY 



Materials needed: ]\Iaps in blank for individual use: 



1. Drainage map of the region (state or province) with streams and lakes indicated. 



2. Local map covering the area to be traversed by the class. 



3. Detail maps of particular bodies of water. 



4. Topographic quadrangles (U. S. Geol. Surv.) 



Work Program: 



1. Study of these maps. 



2. Reading. 



(a) Chapter I in the text, Life of Inland Waters. 



(b) Local geography and hydrography (whatever is available). 



For Record:* 



1. On map 1 mark: 



(a) Your own location. 



(b) The location of any biological field stations, state or national fish hatcheries, 



or other large enterprises of limnological interest. 



(c) Large parks and reservations. 



(d) The principal drainage areas (do this by drawing a red line along the divide 



between principal watersheds). 



2. On map 2 mark the location of: — 



(a) The choice aquatic collecting grounds of your locahty. 



(b) The location of principal springs and marshes, swamps and bogs. 



(c) The falls, dams and swimming holes in the streams. 



(d) The lakes and ponds. 



(e) The more popular fishing grounds. 



3. On detail maps of local hydrography (may be deferred to studies 4 and 5). 



(a) If of a lake or pond or bay, soundings being given, draw contours (with 



appropriate contour interval) and indicate by wash of colors the areas of 

 bottom that differ in character and in vegetation (if known). 



(b) If of a stream, draw a profile (adjusting longitudinal and vertical scale to 



the dimensions of your note book: data for this may be taken from U. S. 

 Geol. Surv. topographic quadrangles). 



* Data for this exercise are to be supplied largely bj' the instructor. 



