xii THE CAYUGA FLORA. 



ons local maps, we found that the maps showing the most nearly cor- 

 rect survey were those in the Atlas of Tompkins Co., by Stone and 

 Stewart. These agreed so well with Professor Fuertes' map in respect 

 to the ground covered by both, that the Atlas was used as a guide in 

 completing our map. The Atlas is almost the only map giving the 

 north line of Ithaca township correctly. Tbe position of roads, rail- 

 roads, schoolhouses, marshes, etc. were verified by personal observa- 

 tion, and town-boundaries by inspection of original records. The 

 task of correctly representing the streams was considerable, as the ex- 

 isting maps were full of errors regarding them. All we can now say 

 is, that after visiting these and making careful observation, we correct- 

 ed a large number of errors and omissions, and our map is much more 

 nearly accurate than the older ones. What every one must look forward 

 to with expectancy, is the completion of the admirable State Survey 

 now in progress under Mr. James T. Gardiner. With that as a basis 

 there will be a possibility of making wholly accurate local surveys. 

 It is believed, however, that such results will bring about few relative 

 changes in our local map. We therefore feel justified in introducing 

 in it a mechanical arrangement by means of which, as applied to this 

 map, the exact location of any natural object may be briefly indicated 

 on any label or permanent record in connection with our botanical or 

 other natural history surveys. After various less satisfactory schemes 

 to meet a long felt need of the writer, and his colleague, Professor 

 Comstock, the latter devised a plan much more simple and useful 

 than the ordinary system of scpiares applied to maps, and at the wri- 

 ter's request he drew up the following explanation of it, which was 

 published in Science, Vol. VII, (1886), p. 352. "Forthe purposes of our 

 local survey a well-known point on the University grounds is taken 

 as a centre. Upon a map of this locality, a north and south line and 

 an east and west line are drawn through this point. These lines are 

 marked o. Other lines are drawn parallel to these lines dividing the 

 map into squares, each line indicating the distance of one kilometre, 

 These lines are numbered, beginning in each case at the one next the 

 zero line and reading toward the margin of the page. By means of roads> 

 streams and other conspicuous objects, the position on the map, of any 

 locality can be easily ascertained ; and its distance north or south of 

 one zero line, and east or west of the other, seen at a glance. It is 

 only necessary to write figures indicating those co-ordinates upon a 

 printed blank label to accurately indicate the locality. This label 

 should have printed upon it the name of the centre of reference ; it 

 may also have letters indicating two of the cardinal points of the 

 compass. In the latter case four sets of labels would be necessary. 

 The following is an example : — 



Cornell IT. "I «. . ... , . . . . , r ,. f Cornell II. 



N p ( I his filled out might read as follows: W ,, j? ,51/ 



This system was suggested to me by the way in which localities are 

 indicated in the city of Washington." 



The central point taken for our map, and one whose latitude and 

 longitude are accurately known, is the Cornell University S. S. e locat- 

 ed a short distance south of Morrill Hall. It makes the University 



