Recognizable by its peculiar pallid, sessile sporangia, as by the internal structure. Perhaps related to _Hemiarcyria bucknalli_ Mass. Our specimens are from Mr. Morgan, of Ohio, with the statement that they were collected in the San Bernardino Mountains, California, by Mr. S. B. Parrish; collected later from Monterey south. Common throughout south-western states to lower California. =2. Calonema= _Morgan._ 1893. _Calonema_ Morgan, _Jour. Cin. Soc._, p. 33. Sporangia sub-globose, crowded or superimposed, irregular sessile; hypothallus none; capillitium of slender tubules, arising from the sporangium base, branched, marked with branching veins in an irregular reticulation, and terminating in free extremities. Spores yellow. 1. CALONEMA AUREUM _Morgan._ PLATE XIII., Figs. 2, 2 _a_, 2 _b_, 2 _c_. 1893. _Calonema aureum_ Morgan, _l. c._ Sporangia crowded or heaped in scattered clusters; peridium thin, golden yellow, adorned with intricate radiating veinlets capillitium of threads more or less branched, attached below, free above, the surface to the very tips venulose, interrupted with rings or fragmentary spirals, the apices bulbous and obtusely conical; spore-mass yellow, spores by transmitted light bright yellow, covered by a network of interlocking plates, as in _T. favoginea_, globose, 14-16 mu. A curious form, related to _Hemitrichia_, much as _Oligonema_ is to _Trichia_. Related to both the genera first named, but distinct, in the peculiar sculpture, from _Hemitrichia_, and from _Oligonema_ in that the threads are not entirely free. Professor Morgan's original determination, founded on Ohio materials is confirmed by material sent us by Professor Underwood from Alabama. =3. Trichia= (_Haller_) _Rost._ 1768. _Trichia_ Haller, _Hist. Stirp. Helv._, III., p. 114, in part. 1875. _Trichia_ (Haller) Rost., _Mon._, p. 243. Sporangia distinct, sessile or stipitate; capillitium of distinct elastic threads, free acuminate at each end, yellow or more rarely reddish or brown; spores generally yellow. The trichias are easily recognized among their kind by their beautiful spirally wound, elastic capillitial threads, the _elaters_; these are entirely free, about 3-4 mm. in length, simple or only rarely branched, and generally acute at each extremity. The spiral bands, sometimes called _taeniae_, are generally very uniform in thickness, distance from each other, and pitch, and in many species are further reenforced by minute longitudinal plications running from one spiral to the next. Furthermore, the spirals may be smooth or spinulose the elater uniform throughout or enlarged betimes by nodes and swellings. Taken altogether, the trichias with the species of the genus next following exhibit the highest degree of differentiation attained by the Myxomycetes.