38 BOTANY OF LA SALLE COUNTY. 



eially of ferns, is great, and many of them are rare, 

 some found only here. This locality is really divided 

 into two fields one extending- from the east line of the 

 township to about Lovers' Leap the other from Lovers' 

 Leap to the Vermillion river, some plants being- con- 

 fined to one section, some to the other. 



A fifth and very interesting- locality is that known 

 as the Black Ash Swamp lying- on the south side of 

 the Illinois river about half way between Marseilles 

 and Seneca which has been pretty thoroug-hly explored 

 by our enterprising- and talented friend Mr. Charles 

 F. Johnson, formerly of Marseilles, now of Freeport. 

 Here while some of the conditions are similar to those 

 obtaining- in Deer Park Tp., others are not. Some 

 of the plants are the same while several are peculiar 

 to the locality. 



The valley of the Vermillion river is also in places 

 rich in the variety of plants and the exuberance of 

 the veg-etation and some species are found in these 

 places which seem to occur nowhere else. 



The immediate vicinity of Ottawa offers to the bot- 

 anist a very larg-e variety of plants, a number much 

 greater than is usually found in so restricted an area. 

 Some 350 species of plants belonging- to more than 50 

 orders and some 175 g-enera may be obtained within a 

 radius of two miles of the court house. 



In attempting- to identify a plant first carefully ex- 

 amine it. Notice the stem, leaves, calyx, corolla, 

 stamens and pistils and the number of each of the 

 last two. Then look throug-h the natural orders and 

 decide to which it beltmgs, then look for the genus 

 and then the species. Of some of the families the 

 characters are so very distinct that one cannot make a 

 mistake, as for example the Cruciferae, the Leg-urn i- 

 nosae, the Compositae, but of others the same cannot 



