EXPLANATION OF PLATE XV 



Physarum atnnn Schw., p. 36. 



Fig. i . Sporangia on the favorite habitat, magnified. 

 Fig. i a. Capillitium, x 800. 

 Fig. i b. A single spore, x 1200. 



Physarum nefroideum Rost., p. 41. 



Fig. 2. A group of sporangia, stipitate form, x 10. 

 Fig. 2 a. A single spore, x 1200. 



Physaniiii flavicoinnin Berk., p. 53. 



Fig. 3. A cluster of sporangia, one closed, x 10. 

 Fig. 3<z. A single spore, x 1200. 



Physarum tropicale Macbr., p. 45. 



Fig. 4. Sporangia, x 10. 

 Fig. 4 a. Capillitium, x 800. 

 Fig. ^b. A single spore, x 1200. 



Craterinin ininiitiiin (Leers) Fr., p. 78. 

 Fig. 5. Sporangia, the stalks unusually long, magnified. 



PhysantJii penetrale Rex, p. 55. 



Fig. 6. A group of sporangia; the calcareous crust has fallen in all. 

 Fig. 6 a. A single sporangia, enlarged to show columella. 



Physarum nicaragitense Macbr., p. 43. 

 Fig. 7. A group of sporangia, x 10. 

 Fig. 7 a. Capillitium, strongly calcareous, x 800. 

 Fig. 7 b. A single spore, x 1000. 



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