Reddish or roseate forms sometimes appear in colonies otherwise as described. It differs from _B. affinis_ in the size and character of the spores, in color and character of the capillitium, habit and surface markings. 7. BADHAMIA MACROCARPA (_Ces._) _Rost._ 1855. _Physarum macrocarpon_ Cesati, _Flora_, XXXVIII., p. 271. 1875. _Badhamia macrocarpa_ (Ces.) Rost., _Mon._, p. 143. Sporangia scattered or closely aggregate, crowded globose or sub-globose, generally sessile, rugulose, white; the peridium membranous, white above, below yellowish or brown; capillitium not abundant, thoroughly calcareous, the nodes broad, conspicuous, the connecting tubules rigid; columella none; hypothallus scant or none; spore-mass black, spores non-adherent, by transmitted light bright clear brown, thickly spinulose all over, large spherical, 12-15 mu. Closely resembles externally _B. panicea_, but is easily distinguished by larger and remarkably _spinulose_ spores, in this particular unrivalled in the entire genus. European authors describe both sessile and stipitate forms. American specimens generally are sessile and for the most part closely crowded, almost heaped; but--Prof. Bethel finds this in winter everywhere on fallen rotting stems of Opuntia and on the bases of dead Yucca leaves, still attached. Associated with the typical phase and often _occurring alone on the Yucca_ leaves is a discoidal form which when first sent in (1908) was called var. _gracilis_. Presented alone to one ignorant of its history and associations, it would surely pass for a distinct species. This stalked phase is very delicate; the stipe pale brown, or yellow. See Plate II., Fig. 9. See also Sturgis _Col. Coll. Pub._ XII., 408. 8. BADHAMIA ORBICULATA _Rex._ PLATE XIV., Fig. 4. 1893. _Badhamia orbiculata_ Rex. _Proc. Phil. Acad._, p. 372. 1894. _Badhamia macrocarpa Rost._, Lister, _Mycetozoa_, p. 34 (in part). 1911. _Badhamia orbiculata_ Rex., Lister, _Mycetozoa, 2nd ed._, p. 37 Sporangia stipitate or sessile, orbicular discoidal, irregularly elongated or plasmodiocarpous, averaging about 1 mm. in width, generally stipitate, and when stipitate, flattened or depressed above, plane or slightly umbilicate below; the peridium simple, more or less translucent from the varying number of innate granules, sometimes covered with circular flat masses of lime, gray except the point of attachment to the stipe which is brown; stipe short, black, rough, plicate; capillitium dense at the centre, radiant at the periphery where it meets the sporangial wall, white; spores violaceous black, minutely warted, 12-15 mu.