i88 



RESEARCHES ON FUNGI 



crater-like depressions. Fifty dried discharged sporangia were 

 selected at random and were observed under the low power of the 

 microscope by reflected light, and it was found that the number of 

 depressions in the sporangial wall varied from none at all to six 

 (Fig. 94), as indicated in the accompanying Table. 



Fifty dried discharged sporangia of Pilobolus Kleinii 



No depressions or faint traces 



One central depression . 



Two depressions .... 



Three depressions 



Four depressions .... 



Five depressions .... 



Six depressions, one central . 



Six depressions, irregularly arranged 



12 sporangia 

 8 sporangia 

 5 sporangia 

 7 sporangia 



11 sporangia 

 4 sporangia 

 2 sporangia 

 1 sporangium 



Further observation showed that in dried discharged sporangia 

 of Pilobolus Kleinii, as a general rule, the number of depressions 



in the sporangial wall 

 varies directly with the 

 diameter of the spor- 

 angium, the smallest 

 sporangia having the 

 fewest depressions and 

 the largest sporangia 

 the greatest number 

 „ Ar D-7 I, 7 t-; ••• rru of dcprcssions. In 



Fig. 95. — Pilobolus Kletnii. The upper convex ^ 



surfaces of two large dried discharged sporangia wild cultures where 

 produced by wild fruit -bodies, each with a larger 



central dimple surrounded by smaller dimoles. the sporangia were 



In A there ar3 ten smaller dimples and in j ^^ ^j^ ^^ 



B nine. Magnincation, 100. & 



the artificial pure 

 culture from which the fifty sporangia were obtained, it was 

 observed that the number of depressions in a sporangial wall 

 was often nine or ten and that, as a rule, there was one larger 

 central polygonal depression surrounded by a ring of small 

 depressions (Fig. 95). 



An investigation similar to that just described was made on 



