160 THE MYXOMYCETES 



g. Spores in clusters of 4 or more 8. S. uvifera 



g. Spores not in clusters h 



h. Sporangia over 15 mm. tall, flexuous * 



h. Sporangia under 15 mm. tall, subflexuous to erect j 



i. Sporangia angular in section; columella more or less lateral 9. S. fenestrate 



i. Sporangia terete; columella central 10. S. splendens 



j. Peridial net with coarse meshes, 50-125 n across 11. 5. webberi 



j. Meshes of peridial net mostly less than 50 y. k 



k. Spores under 7 ax in diameter, nearly smooth / 



k. Spores 7 \i in diameter or larger, verrucose m 



I. Sporangia 7-15 mm. tall; ferruginous; spores 5-7 xx 12. S. axifera 



I. Sporangia under 5 mm. tall; vinaceous; spores 4-5 xx. . . . 13. S. smithii 



m. Purplish ferruginous; closely fasciculate; columella often 



with plate-like expansions at tip 14. S. flavogenita 



m. Sporangia in small, scattered clusters or gregarious; colu- 

 mella without plate-like expansions n 



n. Slender, acuminate; columella dissipated below tip of 



sporangium; 7-10 mm. tall 15. 5. carolinensis 



n. Columella ending abruptly below obtuse tip of sporan- 

 gium, 3-7 mm. tall o 



o. Peridial net close-meshed, scantily developed above; usually 



on wood 16. S. pallida 



o. Peridial net very fine, complete; usually on herbaceous 



stems or leaves 17. 5. herbatica 



1. Stemonitts trechispora Macbr. 



N. A. Slime-Moulds ed. 2. 159. 1922. 



1909. Stemonitis fusca Roth, var. trechispora Torrend, Fl. Myx. 141. 



Sporangia irregular, small, fuscous black * to dull black, sessile or 

 nearly so, and more or less coalescent below, free above, 5-7 mm. tall; 

 columella black, tapering gradually to a point beneath the apex and 

 giving rise to a capillitium of few, irregular branches; peridial net open, 

 the meshes uniform in size, several times the spore-diameter; hypo- 

 thallus continuous, well developed; spores nearly black in mass, purple- 

 brown by transmitted light, strongly but irregularly reticulate with 

 20-30 or more meshes to the hemisphere, 10-12 /x in diameter. Plas- 

 modium unknown. 



Stemonitis trechispora was originally named by Berkeley but this 

 name seems not to have been published (see Lister, ed. 3. 133). It is 

 usually entered as a variety of S. fusca, but the very large, reticulate 

 spores seem to be distinctive, and the color and structure are also dis- 

 tinct. A very abundant collection by Mr. Hagelstein, from Long Island, 

 approaches fusca in its separate sporangia, but otherwise seems to 

 belong here. Pending further information it seems best to maintain 

 the species. 



On vegetable debris, Maine, Long Island, Washington, Venezuela. 



