didymium] didymiaceae 125 



stronger scattered warts, 11 to 14 ^ diam. — Torrend Fl. Myx., 

 149 ; Petch in Ann. Perad., iv. 348. Diderma difforme 

 Pers. Disp. Meth.,9 (1797). D. cyanescens'Fv. Syst. Myk., iii. 109 

 (1829). D. liceoides Fr. I.e., 107 ? D. nitens Klotzsch in Sm. 

 Engl. FL, v. pt. 2, 311 (1836). D. chalybeum Weinm. Hymen. & 

 Gast., 592 (1836). D. Libertianum Fres. Beitr. Myk., 28, 

 tab. iv. figs. 16 to 27 (1850). D. Persoonii Macbr. N. Am. 

 Slime-Moulds, 96 (1899). Licea caesia Sclmm. Enum. PI. 

 Saell., ii. p. 219 (1803). L. alba Nees in Kunze & Schmidt 

 Myc, ii. 66 (1823). L. macrospora Schwein. in Trans. Am. 

 Phil. Soc, n.s, iv. 258 (1832). Didymium cyanescens Fr. 

 Symb. Gast., 19 (1817). D. Libertianum de Bary Mycetozoa, 

 124 (1864). Physarum album Fr. Syst. Myc, iii. 147. P. 

 caesium Fr. I.e. Lycogala minutum Grev. Scot. Crypt. FL, 

 t. 40 (1823). Chondrioderma difforme Rost. in Fuckel Symb. 

 Myc, Nachtr., 73 (1873), & Mon., 177 ; Lister in Ann. Bot., 

 iv. 281 ; Mass. Mon., 212. C. liceoides Rost. I.e., App. 

 p. 17 (1876) ; Mass. I.e., 215. 



Var. comatum Lister in Journ. Bot., xxxix. 8. Capillitium 

 profuse, of slender straight branching threads, not thicker 

 below, dark or colourless. — Leocarpus calcareus Link in Mag. 

 Ges. Nat. Fr. Berl., iii. 26 (1809) ? Chondrioderma calcareum 

 Rost. in Fuckel Symb. Myc, Nachtr., 74 (1873) ? 



Pl. 104. — a. sporangia (Lyme Regis) ; b. capillitium and spores, with a fragment 

 of the upper and lower sporangium-wall ; c. capillitium and spores of var. comatum ; 

 d. spore of type. 



This species is here removed from Chondrioderma (syn. Diderma) 

 where it was placed by Rostafmski, on account of the crystalline 

 character of the lime forming the outer crust of the sporangium-wall. 

 The type of Licea macrospora Schwein. from Carolina (K. 1206), 

 named Chondrioderma liceoides by Rostafmski, is a characteristic 

 specimen of the present species. The var. comatum has appeared 

 abundantly throughout the winter months for several years in the 

 neighbourhood of Lyme Regis ; it has also been obtained from Bedford- 

 shire and Cornwall, from Japan and Philadelphia. Besides being 

 characterised by having profuse capillitium, the plasmodiocarps are 

 often larger and more plate-like, and the spores greyer than in the 

 typical form, but these characters are not constant. There is no type 

 of Chondrioderma calcareum Rost. in the quoted collections ; the 

 description in Rostafinski's monograph, however, applies so well to 

 the var. comatum of D. difforme that there can be little doubt it refers 

 to this form.* 



Hab. On dead leaves and herbaceous stems. Very common in the 

 British Isles. — Wanstead, Essex (B.M. 1325) ; Lyme Regis, Dorset 

 (B.M. 1326) ; Welshpool, Wales (B.M. 1062) ; France (K. 386) ; 

 Germany (B.M. 507); Belgium (K. 401); Switzerland (B.M. 1975); 

 Austria (B.M. 1815) ; Italy (B.M. 527) ; Portugal (B.M. 2461) ; India 

 (K. 1466) ; Seychelles (K. 1467) ; Japan (B.M. 2462) ; Philadelphia 

 (B.M. 2463) ; Carolina (K. 1206). 



* The description of C. calcareum Rost. in Saccardo's Sylloge, vii. 370, is con- 

 tracted, and omits any reference to the abundant development of the capillitium. 



