CRATERIUM 93 



matter, 0.3-1.5 mm. high; capillitium of sparingly branched threads 

 or flattened tubes with long narrow orange lime-knots, or consisting 

 almost entirely of slender, rod-like tubes enclosing yellow lime gran- 

 ules; spores rich violet-brown, minutely spinulose, 9-12 /u. Plasmodium 

 yellow. 



The above description, based on that of Miss Lister, as well as the 

 fact that the species was formerly regarded as a variety of P. viride, 

 seems to justify placing it tentatively with the tilmadoches. 



Reported from the West Indies; Central Africa, Malay Peninsula, 

 Japan. 



5. Craterium Trentepohl 

 in Roth, Cat. Bot. 1 : 224. 1797. 



Sporangia stalked, cyathiform, the peridium of two or three layers, 

 the dehiscence more or less definitely circumscissile, or by a distinct 

 lid, the upper portions calcareous, the lower cartilaginous, long-per- 

 sistent as a cup containing the spores and capillitium, the nodes of 

 the latter often aggregated to form a pseudocolumella. 



Very close to Physarum, from which genus it is separated by the 

 form of the sporangia and the method of dehiscence. In some forms 

 there is a tendency to irregular dehiscence, notably in C. leucocephalum 

 var. scyphoides, but even here approximately half the sporangium wall 

 remains as a persistent cup. The capillitium is occasionally bad- 

 hamioid. 



KEY TO THE SPECIES OP CRATERIUM 



a. Dehiscence circumscissile or by the breaking up of the 



upper wall of the sporangium b 



a. Dehiscence by a distinct lid d 



b. Sporangia violet or purple 1. C. paraguayense 



b. Sporangia yellow 2. C. aureum 



b. Sporangia white-capped c 



c. Sporangia subglobose to obovoid 3. C. leucocephalum 



c. Sporangia elongate, cylindrical 4. C. cylindricum 



d. Capillitium entirely white 5. C. minutum 



d. Lime-knots pale brown, small 6. C. concinnum 



d. Lime-knots pinkish or reddish brown, some large 7. C. rubronodum 



1. Craterium paraguayense (Speg.) List. 



Mycetozoaed. 2. 95. 1911. 

 PI. VI, Figs. 129, 130. 



1883. Didymium paraguayense Speg., Fung. Guar. Pug. 1 : 141. 



1893. Craterium rubescens Rex, Proc. Ac. Nat. Sc. Phila. 370. 



1904. Iocraterium rubescens (Rex) Jahn, Hedwigia 43 : 302. 



1909. Iocraterium paraguayense (Speg.) Torrend, Fl. Myx. 174. 



