94 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
The spore plasm has in the meantime become very finely reticu¬ 
lated, and the epiplasm is very coarse. Likewise the spore has 
assumed a regular oblong shape which is retained. The nuclear 
beak retracts, but in so doing the bulb of the fiask is drawn up some 
distance towards the attached end (pi. 10, fig. 51). The centrosome 
has disappeared. A period of growth now ensues for both the spore 
and its nucleus (pi. 10, fig. 52). After the spore has reached about 
its maximum size the exospore is developed, and when this is finished 
the epiplasm is practically exhausted. 
• 
SORDARIA FIMICOLA (ROB.) CeS. tfc DeNoT. 
We owe our knowledge of the cytology of the ascus in the Peri- 
sporiales to the investigations of Professor Harper (’97) on Erysiphe 
communis. Outside of this order the only member of the 
mycetes to receive attention has been Cordyceps ophioglossoides , 
and this at the hands of Lewton-Brain (: 01 ). Unfortunately Lew. 
ton-Brain attempted a cytological investigation on material that was 
not suitably fixed. He even failed to see the nuclei, evidently mis¬ 
taking the nucleoli for them. He states that no formation of spores 
takes place until all nuclear divisions are completed. The nuclei 
then arrange themselves in eight rows, and the delimitation of these 
rows and the separation of their nuclei by septa follow. It is in 
this way that the septate spores originate. 
The writer has examined the same form preserved in Flemming’s 
weaker, and finds that the nuclei possess membranes, chromatin, and 
nucleoli. The only respect in which they deviate from the type is 
in the possession by the fusion nucleus of small cones. These cones 
are extranuclear and lie outside the nuclear wall at opposite poles. 
The nuclear divisions are likewise typical. All the stages in spore 
formation were not followed, but there is reason to believe that the 
young spores are uninucleate, and that the multinucleate condition 
arises by nuclear divisions within the spore. 
The Pyrenomycetes are, in general, for various reasons, difficult 
to manipulate. Of the forms studied none has proved more favor¬ 
able for examination than Sordaria fimicola. The methods em¬ 
ployed in growing material have already been described. 
The ascus most frequently springs from a curved terminal cell of 
an ascogenous hypha, much as in the case of Genea hispidula (pi. 
Pyre no- 
