454 BOTANICAL GAZETTE [DECEMBER 
-Van Tiegh., and that it has been found by him (’8g) in the neigh- 
borhood of Pavia. DANGEARD (:03) has also briefly described the 
development of A. nigricans, which Cavara fails to note. So far 
as I am able to judge from the figures and descriptions of these 
authors, I see no reason for doubting that CLAUSSEN’s fungus repre- 
sents_a new species of Boudiera, as described by HENNINGS. CLAUS- 
SEN grew the fungus on cultures and was able to trace the life history 
from spore to spore. He found that the archicarps consisted of 
antheridia and oogonia spirally coiled together and borne in groups. 
As in Pyronema, the apothecium originates from several pairs of 
gametes. The ascogenous hyphae appear to originate from any or 
all of the cells of the ascogonium. 
The latest work of HARPER (:05), already referred to, traces the 
formation of the sexual organs and nuclear fusion in Phyllactinia 
corylea in the minutest detail, showing that the ascocarps develop 
as the result of fertilization. 
BLACKMAN and FRASER (:06) point out that the non-cytological 
investigation of several forms has shown that a normal sexual process 
is not to be expected in all, and they have therefore undertaken the 
cytological investigation of Humaria granulata, a form in which no 
antheridium is present. They find that the oogonium develops asa side 
branch from multinucleate cells of the mycelium, but that no anther- 
idia are formed as described by Worontn (66). The archicarp 
consists of a varied number of cells, the apical cell of which is much 
swollen and vacuolate, becoming the ascogonium. Investing hyphae 
arise from the stalk cells but no antheridia are developed. The 
ascogonial cell contains a number of nuclei probably formed by divi- 
sion of its primary nuclei. These female nuclei fuse in pairs, thus 
constituting what they regard as a reduced sexual process, similar to 
what occurs in the development of the aecidium of Phragmidium 
violaceum. This vegetative fusion occurs in the ascogonia of various 
ages, and-at no definite stage as in Pyronema. These fusion nuclei 
pass into the ascogenous hyphae, and on account of their size are 
easily distinguished from those of the vegetative hyphae. 
RamLow (:06) has shown that the archicarp of Thelebolus ster- 
coreus arises as a much twisted uninucleate organ from the uninucleate 
cells of the mycelium. No antheridium is developed, but the nucleus 
