654 Fault .— The Cytology of the Laboulbeniales. 
among the Ascomycetes, if the possession of a perithecium is the one 
distinctive character of the Pyrenomycetes, then there is no good reason 
why the Laboulbeniales should not constitute a well-marked subdivision of 
this order. 
The resemblance of the procarp to that of the Florideae, on the one 
hand, and to that of certain Fungi on the other, has long been recognized. 
Cytologically, it stands nearer the latter. The phenomena of conjugate 
nuclear division, and in L. chaetophora of a reduced type of sexuality, 
suggest similar phenomena in the rusts and certain Ascomycetes. 
The nuclear phenomena in the antheridia appear to be of far-reaching 
import. The gap between the exogenous and the endogenous types is 
bridged by such a form as Coreomyces. Such features as a uninucleate 
antheridium, the possibility of proliferation of spermatia from the same 
antheridium, and the exogenous type of spermatium organization, suggest 
similar phenomena in the rusts, many Ascomycetes, and the Florideae. 
But further investigations are needed on the antheridia of all of these 
groups. 
