craterium] physaraceae 97 



C. pruinosum Corda Ic, vi. 13, t. ii, f. 33 (1854). C. Fuckelii 

 Mass. I.e., 272 (1892). G. convivale Morg. Myx. Miami Vallev, 



86 (1896). 



Var. 1. — cylindricum Lister: sporangia cylindrical, nearly 

 white with a reddish-brown base, the wall often without 

 crystalline discs. — C. minimum Berk. & Curt, in Grev., ii. 

 67 (1873); Mass. Mon., 272; Macbride N. Am. Slime- 

 Moulds, 77. C. cylindricum, Mass. I.e., 268 (1892). 



Var. 2. — scyphoides Lister : sporangia turbinate, the wall 

 thickened and rufous at the base, membranous and grey above, 

 dehiscing irregularly and not by a distinct lid. — Physarum 

 scyphoides Cooke & Balf. in Rav. N. Am. Fung., no. 480 ; 

 Mass. in Journ. Myc, v. 186, t. xiv, fig. 7 ; Mass. Mon., 282. 



PI. 82. — a. b. sporangia of various shapes ; the wall of the middle one in 6. is 

 broken and shows a pseudo-columella (England) ; c. sporangia of var. cylindricum 

 (Ceylon); d. sporangia of var. scyphoides (Georgia, U.S.A.); e. spores and capillitiuni 

 with fragment of sporangium-wall showing crystalline discs ; /. spore. 



The yellow crystalline bodies above mentioned are a marked feature 

 in this species. In the typical form they are present in the sporangium- 

 wall, in the lime-knots and columella. They can easily be detected by 

 treating the sporangia with xylol. Those in the wall are either nearly 

 superficial or are embedded in its substance ; they are usually disc- 

 shaped with a crenate margin, measuring 15 to 40 /ul diam., and marked 

 with lines radiating from the centre ; those in the lime-knots are some- 

 what globular, varying from 5 to 20 p- diam., and are often in clusters ; 

 they dissolve rapidly in dilute carbolic acid. The vars. cylindricum 

 and scyphoides have been regarded by some authors as distinct species, 

 but the characters distinguishing them from the typical form of 

 C. leucocephalum are very slight, and many intermediate links occur ; 

 they have the characteristic discs in the lime-knots, but not as a rule in 

 the sporangium -wall. The specimen issued by Fuckel as C. mutabile 

 Fr., Fung. Rhen. Exs. no. 1455 (B.M. 481) (type of G. Fuckelii Mass.), 

 is a subglobose form of the present species with the lime in the 

 sporangium- wall almost absent ; the spores measure 9 to 10 fi diam., 

 and are minutely spinulose. 



Hab. On dead leaves and twigs. Common. — Wanstead, Essex 

 (B.M. 1275) ; Luton, Beds (B.M. 1276) ; Lyme Regis, Dorset (B.M. 

 1277); France (K. 282); Germany (B.M. 471); Switzerland (B.M. 

 2362); Austria (B.M. 2361); Italy (K. 297); Portugal (B.M. 2360); 

 Adirondack Mountains, New York (B.M. 1908) ; Washington State 

 (B.M. 2363) ; Antigua (B.M. 1659) : var. cylindricum— Ceylon (B.M. 

 480) ; Java (B.M. 2361) ; Japan (B.M. 2365) ; Ohio (B.M. 1278) : 

 var. scyphoides — Georgia (B.M. 455) ; Worcester, Mass. (B.M. 2366) ; 

 Galapagos Islands (B.M. 2367). 



5. C. aureum Rost. Mon., p. 124 (1875). Plasmodium 

 lemon-yellow. Sporangia gregarious, obovoid, ovoid or 

 globose, 0-4 to 0-6 mm. diam., stalked, erect, rugose, 

 golden-yellow or greenish, fading almost to white on exposure, 

 without a defined lid, breaking up at maturity in the upper 

 part into areolae, or dehiscing almost to the base in stellate 



