466 BOTANICAL GAZETTE [DECEMBER 
sutum, Geoglossum sp., Verpa conica, Gyromytra sphaerospora, Lepto- 
glossum luteum, Leptoglossum sp., Mitrula phalloides, Leotia lubrica, L. 
chlorocephala (FAULL :05) the ascus grows out from the terminal 
cell, and no uninucleate end cell is cut off. In Verpa bohemica (FAULL 
:05) is found the very greatest variability; the asci appearing as out- 
growths of a terminal cell, or from a second, third, or even fourth cell 
from the tip. 
The lichens Anaptychia ciliaris (DANGEARD :03), and Peltigera 
canina (MarRE :05) have their asci regularly formed according to 
DANGEARD’s method; but Anaptychia ciliaris (MAIRE :05) appar- 
ently develops its asci from the subterminal cells of the ascogenous 
hyphae, while the tips, according to MAIRE, may continue develop- 
ment. Baur (:01, :04), although he does not describe the method 
of ascus formation, figures ascogenous hyphae which are recurved 
in Pertusaria communis. 
In the foregoing I have endeavored to group our knowledge of 
the various methods of ascus formation according to the natural 
classification of the forms investigated, in order that the significance 
of the variation described may be more apparent. It is the nuclear 
history which is theoretically most interesting, and is thus most essen- 
tial to determine the relative ancestry of each of the nuclei which fuse 
in the ascus. This has been done for very few forms as yet. In 
Pyronema, HARPER (:00) has been able to trace the origin of the two 
primary nuclei of the ascus, in a case in which the tips of the ascogen- 
ous hyphae at first contain two nuclei. These divide by simultaneous 
division. Of the four nuclei thus formed, one lies in the terminal 
cell, and two, which are not sister nuclei, in the subterminal cell which 
becomes the ascus. 
Thecotheus belongs to that group of the Discomycetes (Ascobo- 
laceae) whose small fruit bodies are nearly always found growing 
freely on dung. The species in question occurs on horse dung. 
It was found on cultures which were old and partly dried up in 
the Botanical Laboratory of the University of Wisconsin. These 
cultures were kept running, yielding an abundant supply of material 
during the progress of this investigation. The fungus has since been 
found free in nature. The apothecia are very small, about o.5™™ in 
diameter and 0.25™™ high, of a white or yellowish color. When 
