COLLECTING GRASSES IN TENNESSEE, KENTUCKY, 



AND YUCATAN 



By J. R. SWALLEN 

 Section of Grasses, U. S. National Museum 



As Kentucky and Tennessee were less adequately represented than 

 the other States in the grass herbarium of the United States National 

 Museum, I spent the month of June, 1932, collecting and studying 

 the grasses in these two States. The localities visited were Camden, 

 Jackson, Millington, Dyersburg, and Reelfoot Lake in Tennessee, and 

 Mayfield, Morganfield, Leitchfield, and Central City in Kentucky, all 

 in the central or western parts. Species of the genus Panicum are 

 most numerous at that time of the year, and are commonly found in 

 the sandy hardwood forests. 



On July 1, I sailed from New Orleans for Yucatan to collect grasses 

 and grass rusts in cooperation with the University of Michigan and 

 the Carnegie Institution of Washington. I was accompanied most of 

 the time by Dr. William C. Steere of the department of botany 

 of the University of Michigan. The Yucatan flora is known chiefly 

 from the collections of Doctor Gaumer and Doctor Millspaugh and 

 from the early collections of Doctor Schott, none of whom paid 

 special attention to the grasses, so that the opportunity for adding to 

 the known grass flora seemed very promising. The results came up 

 to expectations, as the specimens collected record more than a 50 

 per cent increase in the number of grasses previously known from 

 Yucatan. As the time was limited to little more than six weeks, only 

 a few representative localities could be investigated. It is reasonable to 

 believe that further exploration would add still other grasses, espe- 

 cially in the states of Ouintana Roo and Campeche. 



The state of Yucatan is an almost level plain, unbroken except for 

 a range of low hills near the southern boundary extending from near 

 Muna almost to Peto. Beyond this range to the south can be seen a 

 similar range in the distance. It is said that there are four of these, 

 each succeeding one to the south being higher. In Ouintana Roo and 

 Campeche there are other low hills running roughly parallel to the 

 east and west coast lines. 



Nearly all the peninsula except that which is or has been under 

 cultivation is covered with a very dense growth of small trees. To- 

 ward the south, however, in the states of Quintana Roo and Campeche, 

 where there is more moisture, the growth becomes larger and a little 



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