236 
THAXTER. 
MONOGRAPH OF THE LABOULBENIACE.E. 
KKY TO THE GENERA OF LABOULBENIALES. 
In order briefly to summarise the genera thus far described, the following dichotomous key has been 
prepared which indicates in a general way their supposed natural sequence, as far as this is possible in 
such a summary, and includes a tentative separation of the more pronounced types which have been 
designated by special names designed to suggest the conditions of isolation in the various genera or groups 
genera 
con 
the preliminary matter of this and the preceding Monograph. It will be observed that Distichomyces, 
although at maturity it possesses free simple antheridia, is included among the Peyritschiellacese, where 
it rightly b.longs, and that also H ydrophilomyces is included in the second section, of Ceratomycetinese, 
although its supposed antheridial cells are more or less clearly distinguished. The latter are, however, 
merely corners, as it were, separated from the cells of the main appendage, and later appear to grow out 
into sterile branches as in Coreomyces. Polyascomyces, Smeringomyces and Misgomyces, being of uncertain 
affinities, and their antheridia being unknown, are assigned merely provisional places in the arrangement. 
1. Antheridia specially differentiated cells or groups of cells. 
2. Antheridia compound, the antheridial cells endogenous, arising from 
one or more intercalary cells and discharging into and from a com- 
LABOULBENIINEiE 80 
Dimorphomycetese 
Dimeromyces 
7. 
nam chamber (eventually free in a compact group in Distichomyces) Peyritschiellace,e 
individuals unisexual. 
IVrithecia arising from a primary vertical or oblique axis. 
iVritheeia arising from one or more secondary axes springing from 
the subbasal cell. 
Individuals hermaphrodite, sterile appendages unicellular, subtended 
by black constricted septa. 
35 
7 
6 
Dimorphomyces 
8. Antheridium a free branchlet from the receptacle. 
Antheridial cells discharging through a common pore. 
Antheridial cells becoming free in a compact group. 
Antheridium wholly or partly adnate to the receptacle. 
Cells of the receptacle in tiers above the basal cell. 
T> * 1 • iii 
9. 
10. 
11. 
12. 
13. Perithelia wholly free. 
14. Snbterminal tier of the receptacle bearing paired antheridia. 
15. Snbterminal tier bearing a single antheridium at one side. 
16. 
17. 
IS. 
Rickiese 
Rickia 
Distichomyces 
Peyritschiellese 
20 
11 
10 
18 
IVrithecia more or less adnate to the distal portion of the receptacle. 
Anthendmm anterior at the base of the perithecium 
Antheridium near base of appendages; two cells superposed above 
Dichomyces 
Peyritschiella 
16 
15 
Limnaiomyces 
18 
19 
20 
21 
•> 
Antheridium as in 18, three cells above foot 
Individuals hermaphrodite, sterile appendages multicellular, 
tended by black constricted septa. 
Individuals hermaphrodite, sterile appendages absent 
black subtending septa. 
Antheridium discharging between four terminal appendiculate cells. 
Cltitonomyres 
Hyd rceomyces 
19 
sub- Enarthromy cete se 
or without 
Enarthromyces 
21 
Monoicomyceteae 
25 
