100 PROCEEDINGS : BOSTON SOCIETY NATURAL HISTORY. 
spadicea (pi. 11, fig 80) and Urnula craterium , it looks as if the 
asciis might spring from any cell whatever. The Anixia was 
obtained from a culture given me by Professor Thaxter. 
A number of forms were found to follow very closely the type 
described by Harper and Dangeard. These were Peziza sp., Neo- 
tiella albocincta , Morchella esculenta , M. conica , Helvetia atra , H 
lacunosa , II. elastica , Acetabula sp., Pseudoplectania sp. In 
Hydnobolites and Elaphomyces the ascus usually grows out from 
the second cell, though occasionally the end septum is lacking. 
The cytological phenomena in connection with the origin of the 
ascus are quite readily worked out in the Helvellas, Neotiella, and 
Peziza. Neotiella was found an especially favorable form because 
of the size of its nuclei and the absence of extranuclear bodies. 
The earliest stage of all, however, was observed in Peziza sp., in 
which the hooked end of an ascogenous hypha was found with a 
nucleus in each arm of the hook. These nuclei were also observed 
in a condition of mitosis (pi. 11, fig. 64). Of the four daughter 
nuclei the proximal one is soon shut off by a septum (pi. 11, fig. 65). 
This was the first stage found in Neotiella. A second septum was 
then formed cutting off the distal nucleus (pi. 11, fig. 66) and leav¬ 
ing the two middle nuclei in a penultimate cell. It is from this cell 
that the ascus grows out. The two nuclei fuse either before or after 
they enter the yofing ascus (pi. 11, fig. 69). In Urnula craterium 
the fusion is always effected in the ascus and not until it has attained 
a considerable length. 
This fusion apparently consists in the disappearance of the parts 
of the nuclear walls in contact, and the flowing together of the 
chromatin and the nucleoli. The “ fusion ” nucleus rapidly rounds 
up unless the fusion has taken place in the ascus. When the 
“fusion” nucleus lies in the ascus it is always elongated because its 
diameter is greater than that of the ascus (pi. 11, fig. 68). 
The nuclei of the first and third cells usually disappear very soon 
after the ascus has begun its growth, and the same is true of the 
protoplasm in the cells in which they lie. It is too much to say, 
however, that such is the constant fate of both, and especially of 
the proximal one. The origin of the four nuclei found in the hook 
cannot be stated with absolute certainty. There is reason to believe 
that they may be products of a single nucleus in some cases. Thus 
it is a matter of observation that an ascus-bearing hook may be 
