Stemonitis 153 



but in colonies of uniform sporangia it may be distinguished by 

 the erect, scattered habit, or small clusters of separated sporangia. 

 In mixed gatherings the separation is more diffcult, sometimes 

 impossible. S. carolinensis is one of a number of intermediate 

 forms that may be noticed, and unworthy of distinction. In view 

 of present knowledge of the variation and connecting forms be- 

 tween 6". herbatica, S. pallida, S. flavogenita, and 5. axifera, here 

 recognized as species and centers, it is necessary to discard all 

 others that have only trivial differences in characters. 



10. Stemonitis flavogenita Jahn, Verh. Bot. Ver. Brandenb. 

 45: Abh. 165. 1904. (N. Y. B. G. no. 8672, authentic 

 material.) 



Plasmodium translucent citron-yellow (Lister). Total height 

 4 to 7 mm. Sporangia cylindrical, obtuse, closely clustered in 

 scattered groups, short-stalked, usually rusty brown. Stalk 

 black, 0.5 to 1 mm. high. Columella often ceasing below the 

 summit of the sporangium, sometimes expanded. Capillitium of 

 ferruginous or brown threads springing from the columella and 

 forming a loose network with numerous, broad, membranous ex- 

 pansions; meshes of the delicate surface-net angular, rather un- 

 even, varying from 6 to \6 jx diam., with the threads spinose. 

 Spores pale reddish, faintly warted, 7-9 n diam. 



Type locality: Germany. 



Habitat: On ground material, also on wood. 



Distribution: *California, Florida, New York, *Oregon, 

 Pennsylvania, South Carolina, *Washington. 



Illustration: Lister, Mycetozoa ed. 3. pi. 119, figs. a-d. 



A rare species in North America, and somewhat difficult to 

 distinguish from others to which it is related. It seems to be 

 intermediate between S. herbatica and small phases of 5. axifera, 

 differing from the former by the spinose net of the capillitium and 

 the more reddish spores, and from the latter by the short-stalked 

 sporangia, and the larger size of the spores. The color of the 

 Plasmodium is not an absolutely distinguishing character, as in 

 either other species the plasmodium may occasionally be yellow. 

 The more usual habit of developing on leaves and herbage is 

 helpful, but the expanded tip of the columella is of little value in 

 diagnosis, as it is seen very rarely. The color of the spores is a 

 little darker than those of S, axifera. 



