132 ENDOSPOREAE. [DIDYMIUM 



stalked, sessile, or forming effused plasmodiocarps, snow- 

 white from abundant stellate crystals, which often form a 

 wrinkled deciduous scaly outer crust, or grey when the crystals 

 are more scanty ; in the plasmodiocarp forms the crystals are 

 often sparsely distributed ; sporangium-wall membranous, 

 sometimes mottled with red-brown towards the base, at length 

 breaking up into small fragments. Stalk white or pale yellow, 

 rarely orange, cylindrical, deeply furrowed, rough with 

 deposits of lime in minute crystals, varying much m length, 

 discoid at the base. Columella large or small, white 

 or yellowish, hemispherical, absent in effused plasmodio- 

 carps. Capillitium variable, of slender or coarse threads, 

 either almost simple or branching at an acute angle, colourless, 

 violet, or purplish-brown , usually with dark calyciform 

 thickenings. Spores violet-brown, 8 to 11 /x diam., faintly 

 or distinctly spinulose, the spinules often grouped in clusters. — 

 Fr. Syst. Myc, iii. 118 ; Host. Mon., p. 159 ; Mass. Mon., 

 223 ; Macbr. N. Am. Slime-Moulds, 87. Diderma squamulosum 

 Alb. & Schw. Consp. Fung., 88 (1805). Licea stipitata DC. 

 Fl. Fr., ed. 2, 101 (1815). Didymium effusum Link in Mag. Ges. 

 Nat. Fr. Berl., 42 (1815) ; Rost. I.e., p. 163; Lister Myce- 

 tozoa, 99. D. herbarum Fr. I.e., 120. D. leucopus Fr. I.e., 121. 

 D. costatum Fr. I.e., 118. D. filamentosum Wallr. Fl. Crypt. 

 Germ., no. 2187 (1833) ? D. radiatum Berk. & Curt, in Journ. 

 Linn. Soc., x. 348 (1869) ; Mass. Mon., 229, in part. D. 

 Chondrioderma de Bary & Rost. in Alex. Stroj. &c, p. 89 

 (1872). D. neglectum Berk. & Br. in Journ. Linn. Soc, xiv. 

 83 (1873). D. Fuckelianum Rost. Mon., p. 161 (1875). D. 

 praecox de Bary in Rab. Fung. Eur., no. 367 (1861) ; Rost. 

 I.e., p. 163. D. macrospermum Rost. I.e., p. 161. D. discoideum 

 Rost. I.e., p. 162. D. confluens Rost. Mon., App. p. 22 

 (1876). D. platypus Hazsl. in Oester. Bot. Zeitschr., xxvii. 

 83 (1877) ? D. angulatum Peck in Rep. N. York Mus., 

 xxxi. 41 (1879). D. Cookei Raunk. in Bot. Tidssk., xvii. 

 86 (1888). D. Bonianum Pat. in Journ. de Bot., v. 316 (1891). 

 D. Alexandrowiczii Mass. I.e., 232 (1892). D. Tussilaginis 

 Mass., I.e., 244. D. affine Raunk. I.e., 88, t. v, figs. 3, 4. 

 Physarum confluens Pers. Syn., 169 (1801) ? ; Fr. I.e., 146, 

 in part ? P. alatum Fr. I.e., 132 ? P. Tussilaginis Berk. 

 & Br. in Ann. Mag. Nat. Hist., ser. 4, xvii. 139 (1876). 

 Chondrioderma anomalum Rost. Mon., p. 169. C Alexandro- 

 wiczii, Rost. I.e., p. 169. Chondrioderma Cookei Rost. 

 Mon., App. p. 17 (1876). 



Pl_ 109 — a# sessile sporangia, one is broken and shows the white columella 

 (England) ; b. stalked sporangia ; c. plasmodiocarp form without columella ; d. 

 sporangium with wrinkled crust (Devon) ; e. spore of same, marked with clustered 

 warts ; f. g.h. capillitium and spores of various forms, with crystals from sporangium- 

 wall ; t. spore of the usual form. 



