THE SELAGINELLAE OF NORTH AMERICA.— I. 



By Lucten M. Underwood. 



The plants now known under the name of Selaginella were 

 originally placed in Lyc op odium. Two of our species were known 

 to Linnaeus under the names Lycopodium rupestre and L. apo- 

 dum. In all only twenty-four species of Lycopodium were known 

 to Linnaeus in 1753, and of these only ten have been transferred 

 to the genus Selaginella. In 1810 Willdenow enumerated ninety- 

 two species of Lycopodium, of which thirty-four now belong to 

 Selaginella. Spring wrote the first important monograph of Sela- 

 ginella in 1848 and included 209 species. This remained the 

 standard monograph until J. G. Baker of Kew revised the genus 

 in 1887, adding largely from Spruce's South American collections, 

 and raising the number to three hundred and thirty-five species. 

 Numerous species have been added since that time and we have 

 now the latest review of the subject in the treatment of Sela- 

 ginella by Dr. Hieronymus, of Berlin, in Engler-Prantl, Die 

 Naturlichen Pilanzenfamilicn in which the number is raised 

 to five hundred and fifty-nine species ! Our two Eastern species 

 represent two series of the genus which have formed the basis for 

 separation into genera and it is not likely that these divergent 

 types will always be held together. Of these Selaginella rupcstris 

 was long held to represent a single species. In 1865 Alexander 

 Braun separated S. tortipila, originally collected by Rugel in 

 North Carolina, and D. C. Eaton described S. Oregana in 1880, 

 though the species had been described fifty years before by Presl 

 under the generic name Lycopodium, with which the species of 

 Selaginella were then associated. Milde, however, in reviewing the 

 ferns of the North temperate regions of the Old World, had in- 

 dicated ten varieties as early as 1867. My own studies in the 

 genus led to the establishment of seven species in 1898 and Dr. 

 Rydberg and Mr. A. A. Eaton have each added a single species 

 to our list. 



About a year ago Dr. Hieronymus of Berlin, took up the 

 group of species involved in Selaginella rupestris and described 

 a large number of new species from all parts of the world, includ- 

 ing a number from our own country. I have already given a list 

 of these in the Fern Bulletin (IX, 50, Jl. 1901). In the recently 



