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THE JOURNAL OF BOTANY 



which all intermediate stages connecting the extreme forms occurred 

 completely justifying- M. Meylan's suggestion. Another case in 

 which these strong and weak forms are closely associated was 

 observed by Mr. E. Brazier in a gathering on dead oak leaves made 

 in June, 1920, near Stourbridge, Worcestershire. Here the var. 

 debile has a colourless network of widelv expanded threads, and 

 well-formed but very pale grey spores. Without the evidence gained 

 from the Norfolk specimens, it would have seemed quite unreasonable 

 to have regarded this as a form of the stalwart black-spored L. atro- 

 sporitm of the Alps. Such experiences make us realise how far we 

 are from having mastered what the possibilities of variety may he 

 m species of Lamproderma. As the result of these observations, the 

 var. debile must be transferred from L. violaceum to I. atrosporum. 



Hemitbichia obhussea Mevlan, in Bull. Soc Vaud Sc Nat 

 lii. 196 (1919). This name M. Mevlan applies to the form hitherto 

 referred to II. Karstenii Rost., in which the sporangium-walls are 

 translucent and free from all deposits of refuse matter ; it appears to 

 stand in the same relation of Trichia lutescens Lister as H. Karstenii 

 does to T. contorta. 



Arcyria carnea, n. sp. (PI. 558, figs. 2, 2 a, b.) This is the form 

 described as A. cinerea~Pers. var. carnea Lister in Mycetozoa, ed. 2, 

 p. 236 ; it is, however, so constant that it seems better to regard it as a 

 distinct species. The distinguishing features are the clustered flesh- 

 coloured sporangia, with papillose and often reticulated cups, givin- 

 attachment to the capillitium ; the threads of the latter are marked 

 with close-set prominences, arranged in a loose spiral and appearing 

 square-ended or notched when seen in profile ; the remainder of the 

 thread is either spinulose or marked with a broken reticulation or 

 occasionally with three or four faint and irregular spiral bands • the 

 spores are 7 to 8/t diam. In the field A. carnea may resemble 

 robust forms of A. insignia Kalchbr. & Cke., but the capillitium is 

 tar less flaccid in texture than in that species and the prominences 

 are much more strongly developed. I have found it on old stumps in 

 Essex and Hertfordshire ; it has been obtained by M S Buchet 

 ni the Forest of Fontainebleau, by Dr. H. Bonn in Holstein, by 

 Dr. Celakovsky, jr., in Bohemia, and by Mr. K. Minakata in Japan.* 



Both Schumacher and Wallroth published species under the name 

 Arcyria carnea, but with descriptions too brief to be of value • they 

 have been considered by later writers to refer to either A. incarnate 

 Pers A denudata Wettst., or A. cinerea Pers., flesh-coloured forms 

 ot which are not unfrequent It is quite possible that the present 

 species may have been described previously as A. carnea, but in the 

 absence ot types this must remain uncertain. 



Minakatella, n. genus. Sporangia clustered, more or less united 

 into an aethakum. Capillitium forming a coil of nearly simple 

 smooth tubular threads. Spores spinulose 



M. longifila sp. unica (PI. 558, figs/3, 3 a~d.) Plasmodium ? 

 Sporangia sessile subglobose, 0-3 to 0-5 mm. diam., more or less 

 confluent in small clusters 1 to 2 mm. across, dull red with iridescent 

 membranous walls ; where the sporangia are in contact their walls 

 may be imperfectly developed and reduced to irregular strands and 



