182 Journal of the Mitchell Society [March 



culture. The resting bodies are at first dark and liave numerous large 

 oil droplets. As they get older the walls assume a yellowish-brown 

 color and the contents become homogeneous. They appear singly along 

 the branches in sympodial arrangement. 



In a discharging sporangium a few spores that failed to get out 

 were observed to crawl about actively in an amoeboid fashion for a 

 good while. After an hour they had encj'sted and one had sprouted. 



The spores are of a peculiar internal structure, resembling closely 

 those of B. Pringsheimii as shown by Thaxter (1. c. pi. 3, fig. 11). 

 Most of the protoplasm is at the end opposite the cilia, the center is 

 almost clear and the cilia seem to extend down through the clear tip 

 to a protoplasmic mass below, as shown in our fig. 5. 



Chapeu Hill, N. C. 



Explanation of Plate 32 

 Septocladia dichotoma 



Fig. 1. Empty sporangia in chains, x 154. 



Fig. 2. Three sporangia, one discharging spores, two empty, x 420. 



Fig. 3. Vegetative branch, showing short joints and young resting bodies, x 59. 



Fig. 4. Optical section of resting body and empty sporangium with two aper- 

 tures. X 420. 



Fig. 5. Two spores showing cilia, x 1296. 



Fig. 6. Spores showing amoeboid movement before encysting, x 810. 



Fig. 7. Sprouting spores, x 1008. 



Fig. 8. Habit sketch, showing empty sporangia and resting bodies, x 96. 



Fig. 9. Vegetative tips, showing refractive bodies and clear blunt tips, x 150. 



Fig. 10. Optical section of mature resting body with empty sporangium below. 

 x 420. 



Fig. 11. Long, slender thread on corn grain, showing sympodial arrangement 

 of resting bodies, x 96. 



Fig. 12. Surface view of resting body, showing pits, x 420. 



Fig. 13. Part of branch, showing thin sheath out of which the resting body 

 (Fig. 12) has slipped, x 420. 



Fig. 14. Section of thick wall of the resting body, showing the pits and the 

 sheath outside, x 1296. 



Fig. 15. Mature sporangium just before discharge of spores, x 420. 



Fig. 16. Group showing some sporangia before maturity and some after empty- 

 ing. X 96. 



