90 
Notes. 
the hyphae, especially where rapid growth is taking place, the proto- 
plasm is much denser, and almost completely fills the cavity of the 
filament. The nuclei possess the same structure as those of the 
higher plants, and do not differ in any fundamental respect from 
those described by me as occurring in the mycelium of the Hymeno- 
mycetes. Each nucleus consists of a nuclear membrane, a network 
of linin which contains very little, if any, chromatin, and a nucleolus. 
In the formation of asexual reproductive organs, protoplasm and 
nuclei pass into the club-shaped sporangiophores. A part of this 
protoplasm accumulates at the apex together with four or five nuclei. 
This is then separated by constriction of the cell-membrane and the 
formation of a double cell-wall, the sporangium being thus from the 
beginning a multi-nucleated cell. No fusion of the nuclei is to be 
observed in these basidia, as has been described in the basidia of the 
Hymenomycetes both by Rosen and myself. 
The formation of oogonia takes place by terminal or intercalary 
swelling of the hyphae, into which large quantities of protoplasm pass 
together with nuclei. The nuclei appear to be plastic, inasmuch as 
they become irregular in shape during the rapid rush of the protoplasm, 
and appear at first in the young oogonium as knots in the protoplasm. 
According to Fisch the oogonium contains from ten to twenty nuclei, 
but I find a much larger number than this — 75, 88, 97, and 1 15 having 
been counted in different oogonia. After an oogonium has been cut 
off it becomes turgid, the nuclei regain their shape, and they are then 
seen to be similar in size and appearance to those in the mycelium. 
They do not long retain this appearance however, but begin to increase 
in size ; the linin-network stains more deeply, and the nucleolus becomes 
more indistinct. The same changes take place in the antheridium, in 
which about six to twelve nuclei are to be found. 
The protoplasm of the oogonium now tends to contract away from 
the wall except at the place where it is in contact with the antheridium, 
at which point a fertilizing spot appears. The nuclei begin to move 
towards the periphery of the contracted protoplasm, and at the same 
time begin to divide. The division is karyokinetic, an equatorial 
plate and distinct spindle being formed. A deeply stained, finely 
granular mass of protoplasm (mistaken by Dangeard for an oil- 
globule) appears in the central clear part, and close to this is to be 
seen a single nucleus derived from the division of one of the oogonial 
nuclei. This is the nucleus of the ovum : the other nuclei become 
