CONTRIBUTIONS FROM THE CRYPTOGAM IC LABORATORIES 

 OF HARVARD UNIVERSITY. — No. LXIX. 



NEW OR CRITICAL LABOULBENIALES FROM THE 



ARGENTINE. 



Bt Roland Thaxter. 

 Presented April 10, 1912. Received July 28, 1912. 



The rapid accumulation during the past six years of Laboulbeniales, 

 which have come to me from various parts of the world and now 

 include some hundreds of new species and genera, has forced me to 

 abandon ray intention to figure all new forms as they were published ; 

 and it has again become necessary to resort to preliminary diagnoses, 

 a third series of which is entered on with the present paper. It is, 

 however, my purpose to illustrate all the species described in this 

 series as soon as the necessary figures can be prepared and published. 

 The exotic material which is now available is not only very varied, 

 but is in far better condition than that which has formerly been 

 obtained from dried specimens of insects, for the reason that a majority 

 of the hosts have been collected directly into alcohol and the parasites 

 removed before drying. 



The examination of large series of forms in good condition has 

 inevitably led to some modification of my views in regard to the limita- 

 tions of certain genera and species, and while it has in some instances 

 made clearer relationships or differences that were formerly in doubt, 

 it has at the same time served to break down distinctions which were 

 formerly regarded as more or less crucial, so that it has seemed best 

 to modify the treatment of certain genera and species. Thus in the 

 present paper, the limits of Corethromyces, for example, are consider- 

 ably extended to include several genera hitherto kept distinct, and 

 other changes will be noticed applying both to species and genera, 

 which have seemed advisable in the light of a more complete knowledge 

 of numerous forms. 



The materials here considered were collected in Argentina, chiefly 

 in the Buenos Aires region, the host insects having been captured 



