77 



The Highland region, comprising District 4, shows the greatest 

 possible range. It includes rocky steeps, mountain brooks, 

 torrents, springs and ponds, as well as swampy low ground and 

 abundant forests. The Hudson river itself, with its mighty 

 evaporation of comparatively fresh water, produces an ideal 

 atmospheric condition for the growth of many species. That 

 part of Pennsylvania included within these limits, produces by 

 far more foliaceous than crustose forks, owing to its peculiar 

 atmospheric condition and abundant forests. 



It may be fairly concluded, therefore, that no region could 

 afford greater opportunities for the study of lichens, because of 

 its great differences in altitudes, soils, and atmospheric condi- 

 tions. It consequently follows, that no region of equal area 

 produces at the same time such ideal and such poor conditions; 

 and so many common and varied forms. 



Stations 



The lichens listed are all found in the area composed of the 

 above six districts, and are arranged in the order of their im- 

 portance and relationships as originally determined by Tucker- 

 man. The authority, station, habitat, follow. It will be noticed 

 that the station of each district is the one most often mentioned 

 in the list. This because all specimens found within a short 

 radius of the station are named as at that station. 



It will be noted (see map) that the entire area included within 

 the 100 mile radius, has been divided into six districts, each 

 having a station, around which all lichens found in that district 

 have been grouped. 



District i. — This district comprises all of the county of Rich- 

 mond, N. Y., or Staten Island. Richmond, the county seat, is 

 the station. 



District 2. — This district comprises all that part of Long Island 

 west of the 100 mile radius. The station is Cold Spring Harbor. 



District J. — This district consists of all that part of the state of 

 Connecticut within the 100 mile radius. The station is Ellsworth. 



District 4. This district consists of all that part of New York 

 state, north of City Hall, New York, and within the 100 mile 

 radius. The station is Bronx Park, New York. 



