1 



r 



k 



19G MISSOURI BOTANICAL GARDEN. 



While the embankment is ordinarily kept free from plant 



growth and the conditions themselves do not favor vegeta- 

 tion, rosettes and isolated individuals of species occurring 

 along the railroad right of way are found from time to time 

 errowine: in the ballast. 



THE ILLINOIS BLUFF. 



Talus. 

 The talus at the foot of the Illinois bluffs presents the same 



d 



tion studied, 



reasons, Tt 



and 



the base 



the exposure is diametrically opposite. Though one would 

 expect to find as a result that the flora on the Missouri talus 

 was richer in species, the opposite is the case. Plants dis- 

 tributed by railroads are less important on the Illinois talus 

 since this is partially skirted by a local line only. 



TVif. nrinninnl nln.nts ornnrrino- on the Ilhnois talus but lack- 



'lorum 



diphyllum, Arahis confmis, Viola striata, Hypericum Ascyron, 

 Epilobium coloratum, Osmorrhiza longistylis, Bidens connaia, 

 Vernonia altisdma, Phacelia bipinnatifida , P. Purshii, Euphor- 

 bia ohtusata and Habenaria virescens. But for the presence 

 of these i)lants there is no difference between the talus on 

 cither side. It is to be noted, however, that large springs, 

 notably Falling Spring, issue from the face of the Illinois 

 bluff, permitting the existence of numerous liverworts and 

 alcae. The occurrence of Chlorotylium mamillosum, which 

 V.W , crs the rocks at Falling Spring with a green felt, is to be 

 noted here. 



to 



The cUff. 



Like the talus, the cliff surface above it shows certain 

 differences when compared with that of the Missouri bluffs. 

 Frequently the shrubs reach up to the top of the bluff. This 

 is well shown by the occurrence, in the upper part, of Del- 

 phinium tricorne and Arabis laevigata, plants which on the 

 Missouri side are limited to the more shaded localities. How- 

 ever, in such portions as are exposed, the flora presents a 



