86 THE MYXOMYCETES 



rarely exceed 12 /x in our material, and mostly range from 9-11 /x. 

 Cooke's specimens, originally collected by Ravenel in (South?) Carolina 

 are still preserved in London. 



Rare in the United States: Reported from Massachusetts, New 

 York, "Carolina," Wisconsin, Iowa, Colorado, Montana, Oregon, 

 California; Europe. Reported from South America, South Africa, 

 southern Asia and Japan, but most reports are probably more than 

 questionable. 



66. Physarum tenerum Rex 



Proc. Acad. Nat. Sc. Phila. 1890 : 192. 

 PI. VI, Figs. 118, 119. 



1899. Physarum obrusseum (Berk. & Curt.) Rost. ex Macbride, N. A. Slime- 

 Moulds 52, n on Rost. 



Sporangia stipitate, spherical, erect or nodding, 0.3-0.4 mm. in 

 diameter; peridium single, membranous, but thickly studded with 

 circular, flattened, yellow granules of lime, dehiscing by petal-like 

 lobes; stipe 1-1.5 mm. long, subulate, slender, opaque, striate and dark 

 below, pale yellow above; columella none; capillitium delicate, of 

 yellow, rounded nodes, connected by hyaline threads, many of the 

 intersections limeless; spores dark brown, delicately warted, 7-8 fx. 

 Plasmodium yellow. 



This delicate Physarum, very fragile and evanescent, seems to be 

 distinct, by reason of its characteristic rounded nodules, from any 

 similar stipitate species. It resembles P. citrinum, but is more slender, 

 the color is grayish yellow, and it lacks a columella. It varies a little 

 according to locality. Ohio specimens are a little larger and have 

 thicker and more calcareous stipes than is usual in those from Phila- 

 delphia. The walls of the sporangia when fully matured generally 

 break into several petal-like segments which finally become reflexed. 



Rare. New Jersey, Pennsylvania, Virginia, Ohio, Louisiana, Iowa, 

 Texas, Montana, Washington, West Indies, South America; Portugal, 

 Rumania, Ceylon, Malay Peninsula, Java, Japan. 



67. Physarum galbeum Wingate 



in Macbride, N. A. Slime-Moulds 53. 1899. 

 PI. IV, Fig. 64. 



1890. Physarum galbeum Wing., Ellis N. A. F. 2491, without description. 

 1892. Physarum petersii Berk. & Curt, ex Massee, Mon. 295, in part. 

 1894. Physarum berkeleyi Rost. ex List., Mycetozoa 47, in part. 



Sporangia scattered, globose, 0.4-0.5 mm. in diameter, stipitate, 

 often nodding, golden yellow, peridium exceedingly thin, breaking up 



