diderma] physaraceae 111 



specimen from Jedburgh (K. 1477) referred to by Rostafinski as typical 

 Chondrioderma Oerstedtii (see Mon., App. p. 21) has the capillitium 

 and the structure of the sporangium similar to Greville's type of D. 

 Trevelyani ; these characters are also present in the types of D. 

 geasteroides Phill., and D. laciniatum Phul. from California. It seems 

 probable that the type of Lepidoderma obovatum Mass. from Sweden, 

 is the gathering of the present species made by L. Romell at Kumla 

 Station in August, 1885 (see Romell Fung. Exsic. no. 100 : K. 459, 

 B.M. 1783) and named by him provisionally " Didymium subcastaneum " ; 

 Mr. Massee's description agrees with the specimen in all respects ; he 

 states that the patches of lime are innate in the sporangium- wall ; this 

 feature is characteristic of the genus Diderma rather than of Lepidoderma. 



Hob. On dead leaves, moss, etc. — Leicester ? ex Herb. Bloxam 

 (B.M. 26) ; Jedburgh, Scotland (K. 1477) ; Northumberland (K. 

 1478); near Edinburgh (Edinburgh Herb.) ; near Berlin (B.M. 1942); 

 Sweden (B.M. 1783) ; Switzerland (B.M. 2419) ; Colorado (B.M. 

 2420) ; California (Edinburgh Herb. ). 



12. D. floriforme Pers. in Roemer N. Mag. Bot., i. 89 



(1794). Plasmodium greyish- white. Total height 1 to 2 mm. 

 Sporangia crowded, globose, stalked, erect, smooth, 0*8 mm. 

 diam., varying from white to ochraceous-brown ; sporangium- 

 wall splitting into several re volute petal-like lobes, pale 

 brown on the inner side, cartilaginous, opaque, with a closely 

 adhering membranous inner layer. Stalks cylindrical, furrowed, 

 0-5 to 1 mm. long, 0*15 mm. thick, ockraceous-brown, often 

 connected below by a weU-developed hypothallus. Columella 

 ovoid or hemispherical, brown, densely calcareous. Capillitium 

 consisting of slender sparingly branching threads with scattered 

 bead-like thickenings, thicker and anastomosing at the base, 

 dark violet-brown. Spores red violet-brown, paler on one side, 

 marked with widely separated obtuse warts, 9 to 11 /x diam. — 

 Macbr. N. Am. Slime-Moulds, 105. Sphaerocarpus floriformis 

 Bull. Champ., 142, t. 371 (1791). S. antiades BuU. I.e., 

 127, t. 368, fig. 2 ? Didymium floriforme Schrad. Nov. Gen. 

 PL, 25 (1797). Diderma spurium Schum. Enum. PL SaelL, 

 ii. 197 (1803). D. lepidotum Fr. Syst. Myc, hi. 100 (1829). 

 Leangium floriforme Link in Mag. Ges. Nat. Pr. BerL, hi. 26 

 (1809). L. lepidotum Ditm. in Sturm Deutsch. PL, Pilze. 43, 

 t. 21 (1817). Physarum antiades Fr. I.e., 135 ? Chondrioderma 

 floriforme Rost. Mon., p. 184 (1875) ; Mass. Mon., 198 ; Lister 

 Mycetozoa, 85. 



PI. 92. — a. sporangia before dehiscence (England) ; b. sporangia after dehiscence : 

 c. sporangia expanded and showing clavate columellae ; d. capillitium and spores ; 

 e. spore. 



The purplish-red spores with strong scattered warts distinguish this 

 species from all forms of D. radiatum. 



Hob. On dead wood. — Epping Forest, Essex (B.M. 1312) ; Middlesex 

 (B.M. 2421); Woburn Sands, Beds (B.M. 2423); Wvre Forest, Worcester- 

 shire (B.M. 2422) ; Germany (B.M. 533) ; Austria (B.M. 2424) ; Xew 

 Jersey (B.M. 1857) ; Ohio (B.M. 1314) ; Iowa (B.M. 817). 



