204 THE NORTH AMERICAN SLIME-MOULDS 



A most common species, on rotten wood everywhere, espe- 

 cially in forests. Recognized generally at sight by its color and 

 fasciculate habit. The peridium shows a tendency, often, to 

 circumscissile dehiscence, and persists long after the contents 

 have been dissipated, in this condition suggesting the name 

 applied by Batsch, vesparium, wasp-nest. The capillitium is 

 remarkably spinescent, the branching of the threads rare. 

 Rostafinski describes the spores as smooth ; they seem to be 

 uniformly distinctly warted. The plasmodium is deep red, and 

 a plasmodiocarpous fructification occasionally appears. 



Throughout the whole range, New England to Washington 

 and Oregon, south to Nicaragua. 



5. HEMITRICHIA STIPATA (Schw.} Macbr. 



PLATE I., Figs. 8, 8 a, 8 b. 



1834. Leanghtm stipatum Schw., N. A. F., p. 258, No. 2304. 

 1876. Hemiarcyria stipata (Schw.) Rost., Mon. App., pp. 41, 42. 

 1894. Arcyria stipata (Schw.) Lister, Mon. Mycetozoa, p. 189. 



Sporangia distinct, crowded, cylindric or irregular, overlying 

 one another, rich copper-colored, metallic, shining, becoming 

 brown, stipitate ; peridium thin, the upper portion early evanes- 

 cent, the base persistent as a cup, as in Arcyria; capillitium 

 concolorous, the thread abundantly branched to form a loose 

 net, with many free and bulbous ends, pale under the lens, 

 marked by three or four somewhat obscure spiral bands and a 

 few wart-like or plate-like thickenings ; stipe very short ; spore- 

 mass reddish, spores by transmitted light pale, nearly or 

 quite smooth, 6-8 /*. 



This species is known at sight by its peculiarly beautiful tint, 

 when fresh, as by the crowded prolix habit of the singular over- 

 lying sporangia. The netted capillitium and the evanescent 

 peridium suggest Arcyria, but there are abundant free tips, and 

 the threads are unmistakably spirally wound, especially in the 

 large, handsome sporangia characteristic' of the Mississippi Val- 

 ley. It is a boundary form unquestionably. The stipe is gen- 

 erally very short, about one-tenth the total height ; sometimes, 



