OF ARTS AND SCIENCES. 29 



IV. 



CONTRIBUTIONS FROM THE CRYPTOGAMIC LABORATORY 

 OF HARVARD UNIVERSITY. 



XVII. — FURTHER ADDITIONS TO THE NORTH AMER- 

 ICAN SPECIES OF LABOULBENIACEiE. 



By Roland Thaxter. 



Presented by W. G. Farlow, March 9, 1892. 



The present paper includes the additions which have been made 

 during the season of 1891 to the previously recorded species of 

 North American Laboulbeniacete, a small number only of new- 

 forms being reserved for later description from lack of sufficient 

 material. Three new genera are represented, — Ceratomyces by 

 two species, Corethromyces and Acanthomyces each by a single 

 species. The genus Heimatomyces, formerly including a single 

 European form, contributes ten species, nine of them new while, 

 lastly, the genus Laboulbenia adds sixteen species, thirteen of 

 which are undescribed. In all thirty species, by which the sum 

 total of American forms is increased to forty-nine. The material 

 examined was collected by the writer partly in Maine, partly in 

 Connecticut; while very important additions have also been re- 

 ceived through the kindness of correspondents, from whom the 

 communication of hosts likely to be infested has been solicited. 

 For such courtesy the writer is especially indebted to Mr. Theo. 

 Pergande, who has sent Coleoptera collected in the vicinity of 

 "Washington, D. C, and to Miss A. M. Parker, for numerous 

 interesting specimens taken at Slaughter, Washington. Mr. J. 

 M. Aldrich has also kindly sent specimens from South Dakota, 

 and Mr. Samuel Henshaw has determined the greater part of the 

 insect hosts. For all these favors, the writer desires to express his 

 grateful acknowledgments. 



The contribution of aquatic forms is of especial interest, the 

 genus Ceratomyces forming a distinct departure from previously 

 described generic types. The considerable addition, also, to the 



