340 
Wager . — On the Structure and 
EXPLANATION OF FIGURES IN PLATES 
XV AND XVI. 
Illustrating Mr. H. Wager’s paper on Cystopus candidus . 
All the figures have been drawn with the aid of the camera lucida, and the 
apochromatic 2-o mm. apert. 1-40 of Zeiss with ocular 8 ( xiooo), except Fig. 28 
which was drawn with ocular 18 ( x 2250), and Fig. 3 drawn with ocular I2( x 1500). 
Fig. 1. Small piece of mycelium showing nuclei and haustoria. 
Fig. 2. Mycelium with sporangiophores containing nuclei, previous to the 
formation of zoosporangia. Fig. 2 a is a sporangium. 
Fig. 3. Sporangiophore with seven nuclei and three more passing in from the 
hypha. Oc. 12. 
Fig. 4. Young oogonium just forming; the irregular shape of the nuclei clearly 
seen and the lines produced by the streaming in of the protoplasm at the base. 
Fig- 5 - Young oogonium soon after its delimitation from the mycelium. An 
antheridium is seen attached to one side and the accumulation of a denser proto- 
plasm is to be seen commencing in the oogonium on the side near the antheri- 
dium. In this oogonium there were 115 nuclei altogether, and about six in the 
antheridium. 
Fig. 6. A later stage than Fig. 5. The nuclear network is distinctly visible, 
and the germinal papilla projecting from the oogonium towards the antheridium. 
Fig. 7. Portion of section of an oogonium at a later stage than Fig. 6. The 
nuclei have much increased in size and the nuclear network is very clear. 
Fig. 8. Section of an oogonium in which the protoplasm has begun to contract 
towards the centre. The nuclei show their chromosomes contracted in the centre 
joint preliminary to division. Thick strands of protoplasm are seen connecting 
the central mass of protoplasm to the wall of the oogonium. 
Fig. 9. Later stage than Fig. 8. Nearly all the nuclei have divided, and are 
collecting at the periphery of the central mass. A deeply stained dense mass of 
protoplasm is seen in the centre, in contact with which is the ovum nucleus, 
produced by the division of one of the original nuclei of the oogonium. 
Fig. 10. An antheridium attached to the wall of an oogonium, just beginning 
to push out its fertilizing tube. A dense mass of protoplasm and several nuclei 
are seen in and near the projection. This dense mass of protoplasm stains 
deeply in a similar manner to that in the centre of the oogonium or young 
oosphere. 
Fig. 11. Further stage of development of an antheridial fertilizing tube. The 
antheridium now contains a large number of nuclei produced by the division 
of those originally present, but the fertilizing tube contains only one nucleus, 
together with a mass of deeply stained protoplasm ; these are passing down the 
sides of the tube towards the apex. 
Fig. 12. A fertilizing tube at a slightly later stage than preceding, showing 
the male nucleus with protoplasm at the apex. 
