20 Introduction 



is the best method for determining type species may well be ques- 

 tioned, but it seems to the writer that a universal method for 

 such procedure is desirable, and since many American sys- 

 tematists are using it, it has been used here. However, the use 

 •of the genus Lachnea Quel, is a departure from following these 

 rules. A genus of flowering plants, Lachnaea L., is older. For 

 the purposes of such a paper as the following, it was thought 

 best to make no change in a genus on the grounds of priority, 

 at least not until the cryptogamic genera have been carefully ex- 

 amined by some one with abundance of time and bibliographical 

 facilities. 



All microscopic drawings were made with the aid of a 

 Bausch and Lomb camera lucida. In drawings showing the 

 structure of the sterile tissues of the apothecia, the lines were 

 followed as far as possible with the camera and very little was 

 done free hand. Where all of a section could not be seen in the 

 field with the desired magnification, and it was necessary to 

 move the section, a break was left in the drawing as in Plate II, 

 figures 2, 3, and 4. All drawings were made from free-hand 

 sections of fresh material or from the plant as growing. 



The species marked -\- have not been previously reported 

 from southwestern Ohio. 



Herbarium specimens of all except two or three species are 

 preserved in the herbaria of Freda M. Bachman and Bruce 

 Fink. Nearly full sets are also deposited in the Lloyd museum 

 at Cincinnati, Ohio, and in the herbarium of W. G. Stover. 



The writer is indebted to Dr. H. Rehm, Rev. Giacoma Bres- 

 adola and Dr. Narcisse Patouillard for determining some of the 

 more difficult species ; to Prof. F. J. Seaver for suggestions as to 

 culture methods; to Mr. C. G. Lloyd for the use of literature and 

 specimens in the Lloyd library and museum at Cincinnati, Ohio ; 

 to Mr. Wm. Holden, librarian, for looking up literature; to Mr. 

 P. L. Ricker for several citations and types, and to Dr. Bruce 

 Fink, under whose direction all of the work was done, for kind 

 advice and most helpful suggestions. 



Freda M. Bachman. 



Miami University, Oxford, O., Aug. 31, 1908. 



