424 
TRANS. OP THE ACAD. OP SCIENCE. 
A Revision of the North American Species of the Genus 
Juncus, with a Description of new or imperfectly known 
Species . By George Engelmann, M.D. 
The difficulty I found in arranging the species of Juncus 
of my own herbarium, the doubts in which the authors left 
me by incomplete and unsatisfactory descriptions and by 
confusion in the names and synonyms, the want of confidence 
which all my correspondents, even such as had paid a good 
deal of close attention to it, seemed to place in themselves 
and their own judgment when this genus was under discus¬ 
sion—all this induced me to enter upon a critical study of our 
Junci. I was greatly aided by the most liberal contribution 
of specimens and of observations from all sides; among 
those to whom I am thus indebted I mention Prof. Asa 
Gray, of Cambridge, and Messrs. E. Durand, C. E. Smith, and 
Prof. Leidy, of Philadelphia, who sent me their own and the 
herbaria of the institutions under their care; Dr. J. W. Robbins, 
of Massachusetts; Rev. O. Brunet, of Quebec; Dr. H. P. 
Sartwell, of New York; Prof. T. C. Porter, of Pennsylvania; 
Mr. M. S. Bebb, of Washington; Rev. M. A. Curtis, of North 
Carolina; Mr. W. H. Ravenel, of South Carolina; Dr. A. W. 
Chapman, of Florida; Mr. E. Hall, of Illinois; and last, but 
not least, Prof. W. H. Brewer, of the Calafornia State Sur¬ 
rey, and my indefatigable'and ever obliging friend, Mr. H. 
N. Bolander, of San Francisco. In Europe I was greatly 
assisted by Prof. Caspary, of Kcenigsberg, who compared 
E. Meyer’s herbarium, and by Prof. A. Braun and Dr. Garcke, 
of Berlin, who examined Willdenow’s and Kunth’s herbaria 
forme. My very particular thanks are due to all of them. 
Michaux’s and Lamarck’s plants have, thus far, been inac¬ 
cessible to me, and thus some questions of synonymy must 
remain unsettled for the present. 
A very conscientious examination of over a thousand speci¬ 
mens from all parts of the country, with careful dissections 
of their flowers and fruits, and drawing of these details, has 
enabled me, I believe, to place the proper value on the 
characters derived from the different organs of these plants, 
and to arrive at definite conclusions in regard to their species 
and varieties and their affinities among themselves. 
These investigations, to be sure, were all made “in the 
closet” since the end of last summer, but I trust that they 
are not the less reliable, and that those who have the oppor¬ 
tunity will follow them up in the field, and will enable me 
not only to improve upon this paper, but also to publish, 
with their aid—which some have already promised me—an 
j Herbarium Juncorum Roreali-Americanorum normale^ which 
