SO MYXOMYCETE9. 



with lime, or more rarely central, free, thin-walled vesicles, filled 

 with lime. In the stipitate forms the colnmella is either a vari- 

 ously-shaped prolongation of the stem, penetrating into the interior 

 of the sporangium, or the colurnella consists of a vesicle separated 

 from the sporangium and tube of the stem by a peculiar membrane. 

 Vesicle sometimes divided into numerous cells filled with lumps, 

 or crystals of lime ; sporangia simple, rarely sethaliam or plasrno- 

 diocarp. Rtfki. Mon., 150. 



6fensl2. DIDYMIUItt. Schrad. 



Walls of sporangia single or double, outer wall covered with 

 crystals of lime, either scattered singly over the surface, or com- 

 pacted into a crustaceous separable coating ; sporangia sessile or 

 stipitate, without or with a colnmella, always splitting irregularly, 

 now and then plasmodiocarpous. Rtfki. Mon., 1GO. 



Sub-Gen. 1. Serpularia. 



Plasmodiocarp with single or double walls. 



28. Didymium complanatum. (Bat.) 



Plasmodiocarp either cushion-like, flattened, scattered, or else 

 vein-like, creeping, now and then combined into an irregular net- 

 work ; surface covered with grey, but not numerous, crystals ; 

 capillitium of very thin threads combined into a dense net, remain- 

 ing behind in connection with peculiar large cells ; spores bright- 

 violet, nearly smooth, -0075-'008 mm. diam. Rtfki. Mon., 151. 



On leaves, &c. (Figs. 166. 180.) 



Lijcoperdon complanntum, Batsch., t. 170 (1786). 

 Didymium serpula, Fr. S. M , iii., 126 (1829) ; Eng. Fl. v., 314; 

 B. & Br. Ann. Nat. Hist,, No. 1035 ; Cooke Hdbk., No. 1134. 

 Physarwn confluens, Fckl. Sym. Myc., p. 342 (1869), non Pers. 



Sub-Gen. 2. Cionivm. 



Sporangia with single-wall, columella, or, when this is absent, the 

 stem black, more rarely rusty-coloured. 



29. Didymium clavus. A. 4- S. 



Sporangia hat-shaped, flattened, convex, plane at the base, grey- 

 ish-white, without colnmella, stipitate; stem short, blackish-brown, 

 shining, seemingly smooth, erect ; capillitium of simple threads, 

 or rarely furcate, fusiform, bright-brownish, uncoloured at both 

 ends ; spores bright-violet, smooth, 'OOG5--0083 mm. Rtjki. 

 Mon., 153. 



On various substances. 



Reticularia liemispherica, Bull., t. 446, f. 2 )1791). 

 Plnjsarum clavus, A. & S., t. 2, f. 2 (1805). 



