178 THE MYXOMYCETES 



9. Comatricha cornea G. List. &" Cran. 



Jour. Bot. 55 : 121. 1917. 



Sporangia scattered or solitary, stalked, globose, 0.12-0.32 mm. in 

 diameter; stalk subulate, straight, slender, 0.17-0.2 mm. high, dark 

 brown above, brownish yellow below where it expands into a discoid 

 hypothallus; columella brown, cylindrical, reaching one-third to one- 

 half the height of the sporangium, with a small collar where it meets 

 the stalk, dividing above into two or three primary branches of the 

 capillitium; branches forking repeatedly and ending at the surface in 

 short, rigid, diverging branchlets; spores gray, minutely warted, the 

 spore wall thinner on one side, 8.5-9 fx. 



Scotland, Germany, Switzerland. 



10. Comatricha fimbriata G. List. & Cran. 



Jour. Bot. 55 : 122. 1917. 



Sporangia scattered, stalked, globose, blackish brown, 0.1-0.35 mm. 

 in diameter; stalk black, subulate, slender, straight or curved, 0.5-1 

 mm. high; capillitium arising chiefly from the summit of a short 

 truncate columella, consisting of a scanty tuft of purplish brown 

 threads, extremely slender at the base, simple or forking below the 

 clavate or irregularly expanded tips; spores grayish purple, closely and 

 minutely spinulose, paler and smoother on one side, 10-12 yu. Plas- 

 modium colorless. 



Collected from several localities in Iowa by Mr. H. C. Gilbert and 

 the junior author on the bark of trees brought into the laboratory 

 where it develops after a few days in a moist chamber. The curious 

 capillitium is like that of no other species. Aside from the Iowa collec- 

 tions, known only from England and Scotland. 



11. Comatricha suksdorfii Ellis & Everh. 



Bull. Lab. Nat. Hist. Washburn Coll. 1 : 5. 1884. 

 PL XII, Figs. 291, 292. 



1892. Stemonitis suksdorfii (Ell. & Ev.) Massee, Mon. 76. 

 1894. Comatricha obtusata Preuss ex List., Mycetozoa 117. 

 1907. Comatricha nigra (Pers.) Schroet. var. suksdorfii Sturgis, Colo. Coll. Pub. 

 Sc. Ser. 12 : 33. 1907. 



Sporangia scattered in small tufts or gregarious, cylindric or clavate, 

 obtuse at both ends, black, 2-6 mm. tall, stipitate; stipe jet-black, 

 shining, even, usually about one-half the total height, sometimes 

 shorter; hypothallus not continuous, dark brown; columella black, 

 rather slender, terminating in two or more large branches just below 



