304 Wager. — On the Structure and 
and finally disappear. The protoplasm swells up again and 
becomes divided into spores by lines of granules which soon 
become converted into continuous cell-walls. Each of the 
spores thus produced contains a clear spot as already described 
by De Bary. The spores then escape from the sporangium, 
remain in connexion with one another for a short time, and 
then swim away. 
Zalewski (’83) described the formation of the sporangia. 
The rounded summit of the basidium becomes superficially 
constricted and swells up until it attains the size of the 
basidium. At the level of the constriction a thin layer or 
border of cellulose appears, which grows gradually towards 
the centre and forms a transverse partition. When this 
division wall has attained its definite thickness, it divides 
into three layers, one of which belongs to the basidium, and 
another to the sporangium. These are separated by a third, 
which becomes gelatinous. This jelly-like membrane colours 
rose-yellow with iodine and sulphuric acid ; the membranes 
of the sporangia and basidia are coloured blue. This jelly 
increases in volume and acquires its largest development 
when the sporangium is individualized. It becomes gradually 
resorbed as the sporangia develop, until only a very small 
portion is left between them in joining them together. On 
the addition of a small quantity of water the jelly is entirely 
dissolved and the sporangia become free. The jelly is also 
capable of absorbing moisture from the air, and is thus able to 
swell up and set the sporangia free. The chain of sporangia 
is now surrounded by a thin membrane which grows in and 
gradually separates them by forming the gelatinous sub- 
stance which connects them together as De Bary at first 
thought. 
In the same year (’83) Zalewski, in another memoir, gives 
an account of his observations on the structure and life history 
of Cystopus , in which he describes the formation of the conidia 
(sporangia) again, and the structure and development of the 
oospore as observed on living specimens. In connexion 
with the formation of zoospores he makes the interesting 
