196 A Monograph of the Myxogastres, 



of lime in the form of crystals, or more frequently as minute 

 amorphous particles. In the sub-section Physarac, which in- 

 cludes the terminal members of the section, lime is present in 

 very considerable quantity both on the sporangium and in the 

 threads of the capillitium, whereas in the sub-section Didymeae 

 lime is abundant on the sporangium, but absent from the 

 capillitium, although usually present in the columella when the 

 latter is present. The genus Crateriaclica is intermediate 

 between the two sub-sections as regards the disposition of lime. 

 In the genus Diacliaca lime is absent from the sporangium, 

 although present in quantity in the columella and stem ; this 

 genus, as explained later on, forms a connecting link between 

 the present section and the CohLmellifcrae, and as such, does 

 not come within the diagnosis of either. Owing to rigidity 

 due to the abundance of lime, especially in the sub-section 

 Pliysarae, there are no marked contrivances for spore dispersion, 

 which appears to be effected by wind on the dissolution of the 

 sporangium, but in the Didymeae, where the capillitium is free 

 from lime and possesses a certain amount of elasticity, the 

 sporangium frequently dehisces in a definite manner. 



Badhamia. 



I 

 Craterium. 



I 



Leocarpus. 



I 



ClENKOWSKTA. PhYSARUM. 



i 



TiLMADOCHE. 



I 



Chondrioderma. Crateriachea. 



I I 



DiDYMIUM. FULIGO. 



I I 



Lepidoderma. Spumaria. 



I 1 



DiACHAEA. 



LITHODERMEAE. 



(Lamproderma. \ 

 COLUMELLIFERAE.) 



