322 METHODS IN PLANT HISTOLOGY 
18. Zygnema. —Stain in iron-haematoxylin, and mount in Venetian turpen¬ 
tine. 
19. Spirogyra. —Stain in Magdala red and anilin blue, and mount in Venetian 
turpentine. 
20. Vaucheria. —Stain in iron-alum haematoxylin, and mount in Venetian 
turpentine. 
21. Char a. —Cut paraffin sections of the apical cell, oogonia, and antheridia. 
PHAEOPHYCEAE 
22. Ectocarpus — Stain some in iron-haematoxylin and some in Magdala 
red and anilin blue. Mount both together in Venetian turpentine. 
23. Cutleria. —Sections of oogonia, antheridia, and sporangia. Cut 10 /a 
thick and stain in iron-haematoxylin with about 7 minutes in safranin. 
24. Fucus vesiculosus . —Antheridial conceptacle with paraphyses and 
antheridia; oogonial conceptacle with oogonia. Cut 10 p thick and 
stain in iron-haematoxylin with about 5 minutes in safranin. 
RHODOPHYCEAE 
25. Nemalion. —Stain some in iron-haematoxylin and some in eosin. Each 
preparation should show trichogyne, carpogonium, and cystocarp. You 
cannot mount it in Venetian turpentine; use glycerin or glycerin jelly. 
26. Polysiphonia. —Stain in iron-haematoxylin or Magdala red and anilin 
blue. Mount whole in Venetian turpentine. Each mount should 
show tetraspores, antheridia, and cystocarps. If material is in paraffin, 
cut sections about 7 p thick. 
FUNGI 
PHYCOMYCETES 
27. Rhizopus nigricans. —Stain young sporangia in eosin, dilute Delafield’s 
haematoxylin, or in Magdala red and anilin blue. Some zygosporic 
material should be stained strongly in eosin: some should be stained 
in iron-alum haematoxylin, and in reducing the stain, some should 
be taken out early to show the coenocytic character of the mycelium, 
and some should be drawn farther to show the structure of the zygospores 
and suspensors. Venetian turpentine. 
28. Saprolegnia. —Stain some in Magdala red and anilin blue, and some in 
iron-alum haematoxylin. Each mount should show sporangia and 
oogonia. Venetian turpentine. 
29. Albugo Candida. —Select white blisters which have not yet broken open. 
Paraffin 8 p. Iron-alum haematoxylin and orange. Oogonia and 
antheridia, 5 p, same stain. 
30. Albugo bliti on Amarantus retroflexus. —Cut out small portions of leaves 
in which the oogonia can be seen in abundance. Paraffin, 5 p. 
