64 Transactions British Mycological Society, 



♦39. D. asteroides Lister matures from a pale creamy yellow 

 Plasmodium tinged with green. This fact was first noticed at 

 Weybridge in a mixed leaf heap at the end of March and the 

 beginning of April 1923. The young sporangia are of the same 

 colour, but after twenty-four hours they turn to a bright orange 

 yellow like those of Badhamia foliicola, which gives place to a 

 cafe-au-lait tint; the sporangium on drying finally assumes a 

 pinkish buff appearance. The outer sporangium wall is usually 

 covered with purple tigrine mottlings which, if very numerous, 

 may give a purple brown effect to the whole growth. Two or 

 three hundred sporangia were found an inch or two below the 

 surface, especially on hornbeam, beech and deciduous cypress 

 foliage of the preceding fall. 



40. Diachea leucopoda Rost. is of frequent occurrence be- 

 tween August and December on dead leaves of holly, holm oak, 

 yew and bramble and even on dead grass. Some of the sporangia 

 show a yellowish brown stalk. 



41. Didymium difforme Duby. Grows commonly the whole 

 year round on all decaying vegetable matter but seems to show 

 a preference for sycamore leaves. 



var. repandum G. Lister appears in Spring abundantly on 

 sycamore, thistle and lime leaves. In March 1922 when the 

 season was very backward a form occurred with strong warts 

 and spines 1-3^1 long on the capiUitium and spores 14 /z. 



42. D. vaccinum Dur. and Mont, has been found in March, 

 June and September on very rotten straw at Horsley. Most 

 probably it could have been obtained at the same spot during 

 the intervening months, but the distance was too great to 

 permit more frequent visits. It was first recorded for the county 

 by Mr E. S. Salmon on old straw at Reigate. 



*43. D. trachysporum G. Lister has recently been published 

 as a new species. It has been observed for the last twenty-six 

 years and was first described under the name of D. trochus 

 var. tenue G. Lister. It is not unfrequent among dead leaves 

 and rotting straw from February to July but is possibly often 

 overlooked on account of its close resemblance to D. difforme. 

 The sporangia are circular or pulvinate, rather flat, sometimes 

 forming branching plasmodiocarps. The outer sporangial wall 

 is very frail and eggshell-like, smooth or slightly wrinkled, 

 breaking away with the inner hyaline wall adhering to it. The 

 spores are very dark and rough, sometimes with a prominent 

 marked ridge; they vary in size from 8 to 12 /a; some have 

 a very prickly aspect and in others the spines are connected 

 at their bases by low ridges, giving an appearance, when highly 

 magnified, of a much broken reticulation. The capillitium is 

 variable, colourless or dark olive brown, simple, beaded, with 



