Phylum Protoplasta [177 



ter 1. c; the genus Trichina does not belong to this family! Order Trichiaceae Mac- 

 bride N. Am. Slime Molds 20 (1899). Family Trichiidae Doflein 1909. Sporangia 

 with pale or yellow spores, the capillitium of free threads, unbranched or sparsely 

 branched, marked with spiral bands. Trichia, Hemitrichia, Oligonema, Calonema. 



Family 13. Physarea Lankester 1. c. Tribes Cienkowskiaceae, Physaraceae, and 

 Spumariaceae Rostafinski op. cit. 9, 13. Families Cienkowskiaceae , Physaraceae, and 

 Spumariaceae Berlese in Saccardo op. cit. 328, 329, 387. Order Physaraceae Macbride 

 N. Am. Slime Molds 20 (1899). Family Physaridae Doflein 1909. Fruits sporangial 

 or aethalioid, with capillitium, both wall and capillitium containing considerable 

 deposits of calcium carbonate. Physarum, with some seventy-five species, is the most 

 numerous genus of Mycetozoa; the little gray sporangia may be spherical or irregular, 

 sessile or stalked. Fuligo septica produces dirty yellow aethalia reaching several cen- 

 timeters in diameter on vegetable trash; observed on spent tan bark, it has the com- 

 mon name of flowers of tan. Badhamia, Craterium, Leocarpus, Chondrioderma, 

 Spumaria, etc. 



Family 14. Didymiacea [Didymiaceae] (Rostafinski) Lankester 1. c. Tribe Didy- 

 miaceae Rostafinski op cit. 12. Order Didymiaceae Lister op. cit. 93. Family Didy- 

 midae Doflein 1909. Family Didymiidae Poche op. cit. 202. Family Collodermata- 

 ceae Macbride and Martin Myxomycetes 145 (1934). Sporangia with deposits of 

 calcium carbonate in the wall and a simple capillitium free of mineral deposits. 

 Didymium, Leangium, Lepidoderrna, Colloderma. 



Order 2. Exosporea (Rostafinski) Lankester in Enc. Brit. ed. 9, 19: 841 (1885). 



Cohors Exosporeae Rostafinski Vers. 2 (1873). 



OrAtr Ectosporeae Y.ng\tr ?>y\\2ih. 2 (1892). 



Order Ceratiomyxaceae (Schroter) Lister Monog. Mycetozoa 25 (1894). 



Subsuborder (!) Exosporinei Poche in Arch. Prot. 30: 200 (1913). 

 Organisms of much the character of the Enteridiea, but the spores forming a single 

 layer on the surface of the fruits. There is a single family with only one well-marked 

 species. 



Family Ceratiomyxacea [Ceratiomyxaceae] Schroter (in Engler and Prantl, 1889). 

 Ceratiomyxa Schroter [Ceratium Albertini and Schweinitz, 1805, non Schrank, 1793); 

 C. fruticulosa (O. F. Miiller) Macbride. The fruits are white pillars, sometimes 

 branched, 1-2 mm. tall, of secreted material. Each spore of the single superficial 

 layer generates a microscopic stalk and ascends upon it before becoming walled. 

 Meiosis then takes place, making the spores 4-nucleate; the chromosome number is 

 cut from 16 to 8 (Gilbert, 1935). In germination, the contents of the spore are re- 

 leased as a single amoeboid protoplast, whose nuclei divide once; the cell then divides 

 into eight, and these generate flagella (Rostafinski, 1873; Jahn, 1905; Gilbert, 1935). 



Order 3. Phytomyxida Calkins Biol. Prot. 330 (1926). 



Class Phytomyxini Engler and Prantl Nat. Pflanzenfam. II Teil: 1 (1889); class 



Phytomyxinae op. cit. I Teil, Abt. 1: iii (1897). 

 Order Phytomyxinae Campbell Univ. Textb. Bot. 71 (1902). 

 Class Plasmodiophorales Engler Syllab. ed. 3: 1 (1903). 

 Order Plasmodiophorales Sparrow in Mycologia 34: 115 (1942). 

 Suborder Plasmodia phorina Hall Protozoology 228 (1953). 

 Intracellular parasites chiefly of higher plants, attacking also algae, Oomycetes, 

 and beetles, being naked multicellular plasmodia producing walled resting cells, 



