MYCETOZOA EECORBED AS BRITISH SINCE 1909 107 



most succeeding years he has found it there in late summer and 

 autumn. Dr. A. 'Adams also obtained an extensive growth, on a 

 mossy beech-trunk, near Looe, Cornwall, in July 1917. It has been 

 recorded from Ceylon and Japan, and recently Mr. A. R. Sanderson 

 has found it at Petaling, Federated Malay States, on the trunks 

 of Hevea hrasiliensis. 



D. DEPLANATUM Fries. In the British Museum Catalogue this 

 is described as a subspecies of D. niveum Host. ; as, however, it is a 

 constant form, always having a scattered plasmodiocarp habit, it 

 seems better to retain for it the name given by Fries, and to regard 

 D. niveum, with its crowded hemispherical sporangia, as a separate 

 species. D, niveum is very abundant on the Alps in spring, and has 

 not been found in Britain. 



D. EADIATUM (L.) Lister var. umhilicatum (Fries). The type of 

 -D. radiatum in the Linnean Herbarium has brown sporangia dehiscing 

 with petal-like lobes : transitional forms occur connecting it with 

 what was described by Fries as D. umhilicatum, a form with pale 

 drab sporangia which burst irregularly. As M. Meylan has pointed 

 out, this pale variety deserves some distinction ; whether it is regarded 

 as a separate species or as a variety of D. radiatum is a matter 

 of little consequence (" Myxomycetes du Jura " in Ann. du Con- 

 servatoire de Geneve, 1918, p. 312). 



D. RADIATUM var. montanum Mejdan {op. cit. p. 312). In this 

 variety the outer layer of the sporangium-wall is white and separates 

 easily from the membranous inner wall ; the spores are usually 

 rather smaller than in the tvpical form, and measure 7 to 9 ju instead 

 of 9 to 11 ^. 



D. ASTEROIDES Listcr was first found in Britain in October 1910 

 by Mr. W. H. Burrell, who gathered it on the stems of Eciuisetum 

 palustre on marshy ground on Flordon Common, Norfolk, It has 

 since been obtained by Mr. W. B. Allen in Shropshire and by 

 Mr. N. Gr. Hadden in West Somerset. It was also found in abun- 

 dance in a deep bed of holly-leaves in woods at Cawdor, Nairnshire, 

 in September 1912, by members of the British Mycological Society. 

 Outside Britain it has been recorded from Portugal, the South of 

 France, Switzerland, N. Germany, and Colorado. 



Leptoderma iridescens G. Lister in Journ. Bot. 1913, p. 1, 

 pi. 524. fig. 1. This was first found in March 1892 on pine bark 

 and needles at Leighton Buzzard, Bedfordshire, and was named by 

 my father provisionally Lamproderma physaroides Rost. var. sessile 

 Lister. In November 1911, Miss K. Higgins discovered a fine 

 growth of the same form in woods at Woburn Sands, Beds, in which 

 all the characteristic features were displayed — namely the sessile 

 habit, the granular deposits in the sporangium-wall, and the dark 

 grey spinulose spores. It was then published as the tj^pe of a new 

 genus. Subsequently it has been obtained at Porlock, Somerset, in 

 Inverness-shire, in N. Germany, and several jmrts of Switzerland. 



Colloderma oculatum (Lippert) G. Lister. The first British 

 gathering was made by Mr. Cran in Aberdeenshire, October 1910. It 

 now appears to be fairly abundant in many parts. In Ej^ping Forest, 

 Essex, it has appeared every autumn since 1911 ; it has also been, 



K 2 



