290 
Mycologia 
at Amherst, Mass. From two figures given by Hine° I am inclined 
to think that he had before him the sporangia of this plant, but 
that was before it had been described, and he did not get any 
further with it. I have found this species a good many times in 
Chapel Hill in springs, brooks and marshes; for example, in Terra 
Cotta Spring, Glen Burnie Farm (Jan. 15, 1913), twice in a 
marshy place near the above spring (once on Jan. 15 and again 
on Jan. 30, 1913), in Howell’s Spring (Jan. 7, 1914), in Howell’s 
spring and the brook below (March 3, 1914), etc. As the plant has 
so far been rather inadequately figured and described I shall give a 
short account of it before describing the new species. The spo- 
rangia, oogonia and antheridia are well shown by De Bary and 
Humphrey, but variations occur that were not observed by them. 
The antheridial cells, as formed in about one half the oogonia are 
unique in position. They arise by the enlargement of the hypha 
immediately below the oogonium and the growth of this segment 
along the base of the oogonium for a short distance. A tube is 
formed near the septum and enters to the egg. As the antheridial 
cell is in close contact with the oogonial wall from the septum out, 
the position of the septum becomes obscured and the oogonium 
seems to be seated at maturity on a large, swollen, basal cell. 
Under high power, however, the original septum may be seen as 
a somewhat thicker disc. This form of antheridium, as shown in 
fig. 1 and in one of the two in fig. 2, is not exactly illustrated in 
either De Bary’s or Humphrey’s figures. From this strictly basal 
and closely pressed antheridium we have in the remaining half of 
the oogonia all sorts of variations. The antheridium may be 
elevated on a stalk that varies from nothing to half the length of 
the oogonium and in very rare cases the antheridium may be even 
of diclinous origin (figs. 5 and 6). The appearance of several 
antheridia on one oogonium is of rather frequent occurrence in 
my cultures. This is not recorded by De Bary or Humphrey. 
From figures 3 to 7 an idea may be gained of the variations ob- 
servable in both antheridia and oogonia. De Bary does not give 
the size of the oospores. I find them to vary from 16.5 to 24 fi, 
with an average of about 19.5 fi. This is a little larger than the 
figures given by Humphrey. 
6 Figs. 6 and 7, plate 5, Amer. Micr. Journal 1. 1878. 
