The Myxomycetes of Eastern Iowa. 139 



obtuse. Stipe shorter than the sporangium, black. Colu- 

 mella rising to the middle or farther, then spreading into 

 many divergent branches; capillitium threads many times 

 branched, anastomosing to form an intricate net. Spores 

 bright violet, smooth, .004-.005. 



The common species everywhere, variable in size and in 

 the structure of the capillitium. The anastomosing twigs of 

 the capillitium form a net of varying intricacy for containing 

 the spores, but the ultimate tips are free. In the arrangement 

 of species in this genus, I follow Dr. Rex, who makes the pecu- 

 liar surface markings of the spores diagnostic. These in the 

 present species, are not absolutely smooth, but under a good 

 lens show, as in Fig. la, Plate VI, minute papilla with a few 

 larger warts distributed here and there. In the species fol- 

 lowing the spores are larger and more distinctly and uniformly 

 warted. The peridium is rarely seen. 



35. CoMATRiCHA PULCHELLA, Bal). Plate VI, Figs. 3, 3a, 



Sd, 2c and 3^. 



Sporangia elongate-ovate or cylindrical, obtuse at apex. 

 Stipe slender, subulate, black, extending as a branching colu- 

 mella almost to the apex of the sporangium, the branches 

 uniting to form a very intricate net. Spores pale, delicately 

 verruculose, .0075-.00S. 



Not common ; occurring in the same situations as the pre- 

 ceding, easily distinguished by its larger, roughened spores. 

 In form the sporangia vary greatly; sometimes short, cylindric 

 almost sessile, then as in Fig. 3, long, stipitate, and slender. 

 The peridium is well developed and forms an evanescent but 

 distinct membrane, Figs. 3c and 3.-/. 



36. CoMATRicHA CRYPTA, Schweinitz. 



Sporangia cylindrical, obtuse, dull opaque, closely gregari- 

 ous. Stipe short, rather stout, extending as columella almost, 



