PHY S A RUM 49 



xxxx. Stipe yellowish, flaccid, sporan- 

 gia leocarpine 45. P. albescens 

 xxxxx. Stipe very short or none, sporan- 

 gia cylindric, brown 



46. P. variabile 

 °° Capillitium nodes yellow or orange-yellow. 

 X. Badhamioid, larger, — to .8 mm. 

 47. P. aur'tscalpium 

 XX. Physaroid, base persistent 



48. P. oblatum 

 °°° Capillitium nodes pure yellow. 



X. Capillitial threads yellow 



49. P. galbeum 

 XX. Capillitial threads hyaline 



50. P. tenerum 

 XXX. Peridium iridescent. 



t Capillitium persistent 



51. P. flavicomum 



tt Capillitium less persistent, 



larger . 52. P. bethelii 



SECTION II. TILMADOCHE 



I. ^thalioid, gyrose or irregular 53. P. gyrosum 



II. Fructification stipitate. 



1. Sporangia irregular, often convolute, involved 54. P. folycephalum 



2. Sporangia simple, nutant, discoidal. 



a. Thin-walled, grey or white . . . 55. P. nutans 



b. Vari-colored, yellow, greenish, orange, etc. 56. P. viride 



1. Physarum serpula Morgan. 



Plate IX., Figs. 6, 6 a, and 6 b. 



1831. Physarum reticulatum Alb. & Schw., Schweinitz, N. A. T., No. 2295. 



1885. Physarum gyrosum (Rost.) Wingate, Ellis, N. A. P., No. 1396. 



1892. Physarum gyrosum Rost., Massee, Mon., p. 307. 



1892. Cienkoiuskia reticulata Rost., Macbr., Bull. Nat. Hist. loiva, II., 2, 

 p. 150. 



1894. Badhamia decipiens Berk., Lister, Mycetozoa, p. 33, in part. 



1896. Physarum srrpula Morg., Cin. Soc. Nat. Hist., p. 101, 



1899. Physarum serpula Morg., Macbr., N. A. S., p. 29. 



1911. Physarum serpula Morg., Lister, Mycetozoa, 2nd ed., p. 81. 



Plasmodiocarp repent, reticulate, forming anon lines, circles, dots, 

 etc., venulose pale yellow, ochraceous, at length whitish, the peridium 

 thin, membranaceous, simple, fragile, but withal persistent, below 



