THE GENUS TRADESCANTIA IN THE SOUTHERN STATES.
Six years' experience with Thrdescantia, both in the field and in the herbarium, has convinced me that there is something funda mentally wrong in the several existing treatments of the genus. Since I became interested in the forms occurring in the Southern States Dr. J. N. Rose has arranged to monograph the North American Commellinaceae and I publish these notes with his knowledge and consent.
Linnaeus described a single North American species, namely, Y. Of American authors, Walter,t Pursh,11 Elliott I and Darby," each described two species, while Chap man* added a third, 7radescantia pilosa. With the exception of Walter all these authors used the same two specific names, apply ing Ventenat's 7radescantia rosca properly and making Tradescantia firciniana elastid enough to embrace everything else savoring of Tradescantia that existed in their respective regions. Walter ap plied the name not to the Linnaean type, but to the form that Ventenat later described as Tradescantia rosea and proposed the name cristata for one of the larger forms which most authors thought was the real Tradescantia Virginiana of Linnaeus, but judg ing from Walter's description I am inclined to think he had in mind a later described species.
Rafinesque's work on the southern Tradesca;ztias must needs be mentioned. This eccentric author described no less than twenty six species and varieties in eastern North America, thus treating the genus from the standpoint of extreme segregation just as the authors mentioned above treated it from the standpoint of ex treme aggregation. Rafinesque apparently founded a species on nearly every specimen he collected and of course his work needs extensive reduction, but to what previously described species to refer many of the Rafinesquian names is a difficult task. How ever, several of the forms he described, prove to be excellent species, for example, Tradescantia brevicaulis which Dr. Morong restored several years ago f and Tradescantia tej7exct which I re store in this paper.
An attempt to segregate the material in an herbarium on the lines laid down in the several different works above referred to must at once prove futile and not until we recognize the several segregates into which the Virginiana type naturally separates it self can we hope for a clear or scientific interpretation of the group from a specific standpoint.