158 MONOGRAPH OF CHAETOMIUM AND ASCOTRICHA 
Cryptogamic Herbarium at Berlin, the University of Padua, 
the New York Botanical Garden, and to the Cryptogamic 
Herbarium at Harvard University. Cultures of several species 
have been sent to the Centralstelle fiir Pilzkulturen at Amsterdam. 
At this point the writer wishes to acknowledge his indebted- 
ness to those who have aided substantially in the completion of 
this work; to Dr. Roland Thaxter, especially, who has at all 
times been ready to encourage and give freely of his time and 
material, and whose helpful suggestions and guidance have made 
this work possible; to Professor W. G. Farlow for the use of his 
herbarium and literature from his private library; to Professor 
С. Е. Atkinson, Dr. J. H. Faull, Dr. L. W. Riddle, Dr. I. F. 
Lewis, Dr. A. F. Blakeslee, Dr. George R. Lyman, Mr. R. H. 
Colley, and Mr. А. Т. Speare, for material for cultures; to Dr. Р. 
А. Saccardo, Mr. George Massee, Dr. С. Lindau, Dr. Charles Н. 
Peck, Dr. J. Dearness, Dr. P. Hariot, Dr. F. Cavara, Dr. C. H. 
Kauffman, Dr. L. H. Pammel, and Dr. Elam Bartholomew, for 
valuable type material and authentic specimens; to Mr. A. B. 
Seymour and to Mr. Piguet for assistance in reference work. 
This investigation was begun in the Cryptogamic laboratories 
of Harvard University under the guidance of Dr. Roland Thaxter, 
and completed in the botanical laboratories of Dartmouth College. 
THE GENUS CHAETOMIUM, HISTORICAL REVIEW 
The contributions of a systematic nature which have been 
made to the genus Chaetomium are numerous and cover a con- 
siderable period dating back to 1817. In the brief summary 
which follows it will be possible to discuss only those which are 
most important and to call attention іп a very general way to а 
host of minor contributions which have been made by writers 
little acquainted with the characteristics of the forms in this 
genus. 
In 1817 Gottfried Kunze (50) published a description of a 
hitherto unrecognized genus and gave to it the name Chaetomium 
(хойтира, a hair). It is of interest to note his characterization 
of the genus, since he clearly discerned some features which 
many later writers have disregarded, while on the other hand, he 
made errors in describing structures which later writers have 
