MYXOMYCETES AND SCHIZOPHYTES 201 



from a pipette, but a less tedious plan is to arrange a siphon so as to 

 secure a similar current. The Plasmodium will creep up the slide 

 against the current, furnishing an excellent illustration of rheotropism. 

 Enough Plasmodium for an illustration may be formed in two or three 

 hours. Examined under the microscope, the preparation should give 

 an excellent view of the streaming movements of protoplasm. 



The following is another method for getting the plasmodia upon the 

 slide : Place the slides upon a pane of glass and upon each slide place 

 a small piece of plasmodium-bearing wood. Cover with a bell jar. 

 Wet blotting paper or a small dish of water included under the jar will 

 help to create the warm, sultry atmosphere necessary. The slides may 

 be covered with the Plasmodium in a few hours. Permanent prepara- 

 tions may be made by immersing the slide in chromo-acetic acid, then 

 washing and staining without removing the Plasmodium from the 

 slide. Acid fuchsin is a good stain for bringing out the delicate strands 

 of the Plasmodium. Iron-alum haematoxylin, followed by acid fuchsin 

 or erythrosin, brings out both nuclei and cytoplasmic strands. 



Some of the foregoing methods are taken from an article by Pro- 

 fessor Howard Ayers in the January and February (1898) numbers 

 of the Journal of Applied Microscopy. Other methods, with directions 

 for various experiments, are given in the same article. 



In 1931, in the American Journal of Botany, Howard published a 

 very effective method of cultivating myxomycete plasmodia. He used 

 oat agar. Cook 30 g. rolled oats, 15 g. agar, and 1 liter of water for 15 

 minutes in a double boiler. Pour into a flask and autoclave at 15 

 pounds for 15 minutes. When nearly cool, pour into Petri dishes. 

 Temperatures from 20° to 26° C. are good for the growth of most 

 plasmodia. 



If the Plasmodia are allowed to dry slowly by exposing them to air, 

 they pass into the sclerotium condition, where they may remain for a 

 year or more. To revive them, place them under moist conditions, 

 but never cover them with water. Within 24 hours they may become 

 active again. 



SCHIZOPHYTES (Fission Plants) 



BACTERIA {Schizomycetes. Fission Fungi) 



Bacteria are studied almost exclusively from the standpoint of 

 health and disease, and bacteriological methods are, largely, those 

 which have been developed for determining species, structure and 

 phylogeny being incidental. The methods of the medical school will 



