220 ENDOSPOREAE [OLIGONEMA 



11 to 16 fx diam., reticulated with broad and pitted bauds, 

 or with narrow bands forming an irregular net, border 

 0-5 to 1-5 /x wide. -Mass. Mon., 170 ; Macbr. N. Am. Slime- 

 Moulds, 221. Trichia nitens Libert PI. Crypt. Ard., Fasc. iii. 

 no. 277 (1834) {non Pers.). T. bavarica de Thuemen Myc. Univ., 

 no. 1497 (1879). T. Kickxii Rost. Mon., App. p. 40 (187U). 

 T. pusitta Schroet. in Conn Krypt. Fl. Scliles., iii. pt. 1, 114 

 (1885). Physarum Schweinitzii Berk, in Grev., ii. 66 (1873). 

 Cornuvia nitensRost. Versuch, 15 (1873). Oligonema bavaricum 

 Balf. & Ber., in Sacc. SylL, vii. 437 (1888). 0. minutulum 

 Mass. in Journ. R. Micr. Soc., 1889, 348 ; Mass. Mon., 171. 



PJ. 164. — d. sporangia ; e. elaters ; /. spore ; (Ardennes ; Mme. Libert's type). 



This species varies in the markings on the elaters and the reticual- 

 cion of the spores ; few gatherings are exactly similar, and great 

 variety is often seen in a single sporangium ; the length of the elaters 

 in some specimens is only about 50 [jl, while in others the average is 

 from three to four times as long. O. nitens is allied to Trichia affinis, 

 in which species similar variations in spores and elaters are sometimes 

 found in sporangia which have been exposed to unusual conditions 

 of development. A remarkable variety appeared in the Botanic 

 Gardens at Leipsic (B.M. 2960, ex. Herb. Celakovsky) in which 

 many of the elaters branch and anastomose while others remain free ; 

 the threads are expanded into irregular vesicles at the axils of the 

 branches, and are marked with ring-shaped thickenings and 

 about four faint spiral bands. O. bavaricum Balf. & Berl. is 

 described as distinguished from the present species by the more 

 distinct spirals on the elaters, but the spirals are quite as distinct in 

 Libert's type ; the spores of the Bavarian gathering vary in size from 

 12 to 16 fx, and the reticulation also varies so as to present from four 

 to sixteen meshes on the surface of the hemisphere. The type speci- 

 mens of O. minutulum Mass., from Algiers (B. 1739), and Physarum 

 Schweinitzii Berk., from Bethlehem, U.S.A. (K. 1738), are typical 

 O. nitens. The descriptions of Trichia Kickxii Rost. and T. pusilla 

 Schroet. agree so perfectly with the character of O. nitens that they 

 are here placed as synonyms of this species. 



Hob. On dead wood.—" Hay-pit," Staffordshire (B.M. 1476) ; 

 Cornwall (B.M. 2958); Scarborough (B.M. 2959); Belgium (B.M.) 

 747); Germany (Strassb. Herb.); Bavaria (B.M. 746); Leipsic 

 (B.M. 2960) ; Algiers (K. 1739) ; Bethlehem, South Carolina (K. 1738) ; 

 Cambridge, Mass. (B.M. 2961) ; British Columbia (B.M. 2962). 



2. 0. flavidum Peck in Rep. N. York Mus., xxxi. 42 (1879). 

 Plasmodium watery- white ? Sporangia crowded or somewhat 

 heaped, ovoid or subglobose, 0*3 to 0-6 mm. diam., shining, 

 yellow ; sporangium-wall membranous, translucent, yellow, 

 marked with minute close-set thickenings arranged in wavy 

 or fan-like lines, which give the effect of delicate stippling. 

 Capillitium scanty or fairly abundant, of short or long, simple 

 or branched threads, varying from 3 to 5 /x diam., often showing 

 irregular swellings, without distinct spiral bands, but marked 

 with close lines of minute warts that usually form irregular 



