16 THE MYXOMYCETES 



1794. Isaria mucida Pers., Roemer N. Mag. Bot. 1 : 121. 



1805. Ceratium hydnoides (Jacq.) Alb. & Schw., Consp. Fung. 358. 



1805. Ceratium pyxidatum Alb. & Schw., Consp. Fung. 359. 



1879. Ceratium fuscum Cooke, Grev. 8 : 60. 



1879. Ceratium roseum Cooke, Grev. 8 : 60. 



1880. Ceratium sphtzt videum Kalch. & Cooke, Grev. 9 : 22. 



1885. Ceratium mucidum (Pers.) Schroet., Krypt. Fl. Schles. 3 (1) : 101. 

 1889. Ceratiomyxa mucida (Pers.) Schroet., in Engler & Prantl, Die nat. Pflanz. 

 1 (i) : 16. 



Plasmodium usually colorless, sometimes yellow, rosaceous, green- 

 ish or bluish; sporophores white or occasionally yellowish, pinkish or 

 bluish, forming on the substratum mold-like patches composed of the 

 simple or branched sporiferous pillars, 1-10 mm. tall, sometimes 

 more; spores borne externally on slender individual stalks, hyaline, 

 very variable in shape and size but commonly oval or elliptical, 

 8-14 X 6-8 fi. 



World-wide in distribution and extremely common, occurring 

 especially after warm showers and in sultry weather. The spores 

 vary from spherical to oval, elliptical and occasionally to pyriform 

 and somewhat allantoid. Some fructifications bear spherical or short 

 elliptical spores only 7-8 fx in diameter, but great variation in 

 both shape and size may be found among the spores borne on a 

 single stalk. Some of these variations are doubtless due to different 

 degrees of maturity. 



Micheli's figure of 1729 is as good as that of Mueller. The latter 

 referred the species to the Linnaean genus Byssus, which included 

 algae as well as fungi. The same thing is true of Tremella, which is 

 now definitely restricted to the Heterobasidiomycetes. All the other 

 genera with which the genus has been associated, down to Ceratiomyxa, 

 are now otherwise applied. Mueller's specific name seems to have 

 undisputed priority. 



The extreme variability of the species has led to the proposal of a 

 number of varieties as well as specific segregates. These all merge 

 into one another, but the following forms seem for the present to merit 

 recognition as varieties. 



Var. arbuscula Berk. & Br. (Ceratium arbuscula Berk. & Br., Jour. 

 Linn. Soc. 14 : 97, 1873). This is a form in which each sporophore 

 has a single short stalk which becomes profusely branched in tree-like 

 fashion. 



Var. filiforme Berk. & Br. (Ceratium filiforme Berk. & Br., Jour. 

 Linn. Soc. 14 : 97, 1873). This variety is characterized by very long, 

 slender sporophores, sometimes unbranched for 3-4 mm. then branch- 

 ing profusely in a tuft at the top, the branches of the neighboring 



