194 



INTRODUCTORY NOTE. 



At the time when my attention was first attracted to the Laboulbeniaceae by the 

 discovery of several new species in the vicinity of New Haven, Connecticut, during 

 the summer of 1890, it included six described genera (two of which have proved to be 

 synonyms), represented by fifteen described species of which one only was from North 

 America ; while, of the remaining- forms, two were from South America and the rest 

 from Europe. To these, however, European writers have since added a single species, 

 while my own observations have served very considerably to increase the total num- 

 ber of forms referable to this family. A greater portion of these additions have already 

 been described in a series of papers which have appeared from time to time during 

 the past few years in the " Proceedings " of the Academy, and serve as a systematic basis 

 for the present monograph, in which will be found enumerated more than one hun- 

 dred and fifty species from various parts of the world, distributed among twenty-eight 

 genera. The labor and time involved in obtaining and studying the several thousand 

 specimens which have been examined in the preparation of this paper and of the 

 accompanying plates, can hardly be appreciated by any one who has not had personal 

 experience of the many difficulties associated with the manipulation and study of 

 these, for the most part, very minute plants. It is, therefore, needless to say that my 

 investigations, carried on as they have been in connection with other occupations, are 

 incomplete and unsatisfactory in many points relating to the structure and develop- 

 ment of certain genera, for the proper study of which sufficient time or material, or 

 both, have not been available ; and although a certain amount has been done in con- 

 nection with the nuclear changes which take place in the sexual organs before and 

 after fertilization, I have been unable, as yet, to reach conclusions concerning them 

 sufficiently definite to warrant their publication. The results obtained, however, 

 although in very many respects imperfect, have served to demonstrate the unlooked- 

 for numerical importance of the group, its great diversity, and, above all, have afforded 

 definite information concerning the course of development of its members, as a result 

 of which their pivotal position among the higher fungi is clearly indicated. 



Of the species enumerated, more than half have been collected in New England by 

 myself and studied while still living, the remainder having been derived from the 

 examination of dead insects in the collections to which I have had access, or from 

 insects sent in alcohol by numerous correspondents to whose kindness I owe very 

 many interesting forms. For such favors I am under special obligations to Miss A. M. 

 Parker, who has sent me many specimens of Carabidae from Washington ; to Prof. 

 0. F. Cook, who has placed at my disposal all the Coleoptera collected by him in 

 Liberia ; to Mr. Theodore Pergande for many interesting specimens collected in or 



