98 Trans. Acad. Sci. of St. Louis. 



down as the Grand Falls, some two or three miles below. 

 On two or three of these excursions Mr. B. F. Bush has 

 accompanied me; and I am indebted to him for the de- 

 termination of a number of the species. 



The picturesque scenery along this part of the creek 

 attracts many picnic parties and campers from Joplin 

 and other nearby towns. The locality has been known 

 to geologists since Swallow first described it in the old 

 Missouri Reports of 1855. In connection with the work 

 of the Geological Survey Professor Broadhead also made 

 a small collection of plants in the vicinity of Grand 

 Falls. The botany of the barrens formed by the chert 

 exposures, scarcely less interesting than the geology of 

 the region that has been studied by both the United 

 States and State Surveys, presents several features 

 worthy of investigation and description. To the en- 

 thusiastic collector the locality is one of special interest 

 on account of the presence of a number of plants that 

 are rare or unknown elsewhere in this part of the coun- 

 try. The peculiar ecological conditions under which 

 the plants grow, and which undoubtedly make it possible 

 for them to maintain themselves against the encroach- 

 ments of the common dominant species that surround 

 them, while at the same time limiting their range strictly 

 to the area occupied by this particular geological for- 

 mation, also offer an interesting field for study. 



In the present paper only a brief sketch can be given 

 of the singular physiographic features of the region and 

 the resulting peculiarities of the local flora. The local- 

 ity is one that would well repay a closer study with a 

 more complete list of plants than that appended, which 

 is based on the results of several hasty collecting trips 

 at various times in the year, although scarcely covering 

 the entire season. However it is intended to include 

 all of the higher plants noted that seem peculiar to the 

 region as well as a number common to the dry woods 

 and prairies surrounding the barrens. 



The geological formation that gives rise to the Shoal 



