90 THE JOUKNAL OF BOTANY 



or dull dirty white. Mr. K. Minakata records the appearance of a 

 large plasmodium on the surface of the ground, near Tanabe, Japan, in 

 October, 1918 ; it was at first white, but turned pale blue " as clear as 

 Amazonite." He sends a coloured sketch of the striking appearance 

 of the plasmodium as it spread in a network of blue veins over the 

 wooden stopper of a " sake " cask, which had been laid on the ground 

 in the hope that sporangia might form on it rather than on the 

 crumbling soil : where the plasmodium dried rapidly the blue colour 

 changed to milk-white, then cream-coloured, and at length to blood- 

 red and blackish. Mr. Minakata refers to on old Chinese tradition 

 that the blood of an innocent victim will reappear year after year on 

 the spot where he was murdered, not as blood-red but as sky-blue in 

 colour, and suggests that blue plasmodium of P. gyrosam emerging 

 from the ground may have given origin to the belief. 



Physarum ovisporum, n. sp. (PI. 558, figs. 1, la, b.) Plasmo- 

 dium white. Sporangia scattered, sessile, white, pulvinate, or form- 

 ing cylindrical, straight, curved, or irregular plasmodiocarps 0'5 to 

 0'8 mm. diam. ; sporangium-wall minutely roughened with rounded 

 deposits of lime-granules, often with smoother ureas where the 

 lime is thinly and evenly distributed. Capillitium consisting of 

 numerous rounded white lime-knots, varying much in size, con- 

 nected by short hyaline threads. Spores rich purple-brown or 

 red-brown, either globose, 9 to 11 /x diam., or oval and 10x12 

 to 13/k-j minutely waited, usually marked on one side with a pale 

 smooth line of dehiscence. Habitat on dead leaves. This rather 

 puzzling form has been met with in late autumn and winter in 

 the neighbourhood of Lyme Regis, Dorset, for the last thirty 

 years ; it has been found also in East Dorset, near Porlock, Somer- 

 set, and at Chingford, Essex. Although apparently allied to P. 

 vernwm Somm. and to P. compression Alb. & Schw., it cannot 

 well be attached as a variety to either of these species. From the 

 former it differs in the minutely granular surface of the sporangium- 

 wall and in the neat rounded lime-knots, and from P. compressttm 

 in the sporangia being always sessile and not compressed. When the 

 spores are oval and marked with a line of dehiscence, they are unlike 

 those of any other species in the genus; they are, however, occa- 

 sionally globose and uniformly thickened. Even then the other 

 distinguishing characters appear to be of sufficient importance and 

 constancy for this form to acquire speciHc distinction. 



Didymium: Trochtjs Lister. By the rule of priority this name 

 must be replaced by D. vaccinwm (Durieu & Montague) Buchet, 

 see Bull. Soc. Myc. de France, xxxvi. 110 (1920). M. S. Buchet has 

 made recently a careful revision of the collection of Mycetozoa in the 

 Paris Museum, and has found there the type of Diderma vaccinwm 

 Dur. & Mont. It was collected near Algiers, in February 1840, on 

 fallen branches of Opuntia. The sporangia are ochraeeous-grey in 

 colour and correspond, M. Buchet finds, in all respects with those of 

 Did// m in m Trochus. This conclusion, as he courteously points out, 

 confirms the suggestion put forward in Mycetozoa, ed. 2, p. 107, 

 based on the resemblance of the illustration of Diderma vaccinwm 

 (in Expl. Sc. Alger, t. 22, figs. 1 a-b) to Didymium Trochus. 



