340 FETCH : 



occasion it developed in a museum jar containing resin in a 

 natural state, i.e., mixed witli fragments of bark : tlie jar had 

 been in tlie museum for some years before the plasmodium 

 appeared, but in all probability the lid had been recently 

 taken off. 



The Plasmodium is pale yellow or orange-yellow. The 

 cylindrical, iimbilicate, stalked sporangia are subject to 

 considerable variation, and some of tlie forms might be 

 considered distinct species if they had not been seen to hatch 

 from the same plasmodium as the normal form. In the 

 " perfect " form the umbilicus is continuous with the hollow 

 stem, and is about O'l mm. wide, but it may be as much as 

 0*75 mm. wide, without affecting the general shape of the 

 sporangium. But further increase in width usually involves 

 a broadening of the stalk also, so that the sporangium becomes 

 pezizoid, or even sessile, on a red- brown hypothaUus ; in the 

 last case it imitates exactly the rosettes of Physarum 

 gyrosum. In botli Physarum gyrosum and Physarella mira- 

 bilis the plasmodium rises in columns which produce a ring- 

 shaped sporangium on S, red-bi'own hypothallus, but while the 

 hypothaUus in the former always collapses and thus produces 

 sessile rosette-shaped sporangia, in the latter it remains, 

 as a rule, erect, and forms a hoUow stalk. The stalk of 

 Physarella varies from a rigid liollow stalk to a sessile 

 hypothaUus. 



The pezizoid stalked sporangia may attain a diameter of 

 2*5 mm. ; the sessile forms are sometimes 6 mm. diameter, 

 and consist of either a red-brown plate of hypothaUus 

 fringed by the wavy, almost horizontal sporangium, or a 

 continuous laterally compressed sporangium forming a closely 

 reticulated pattern. The colour of the sporangium is greenish- 

 yellow, reddish-yeUow, or deep ochraceous ; they are bleached 

 to gray on prolonged exposure to sunhght. One lot, 

 hatched in the laboratory, has oUve sporangia studded, 

 especiaUy at the top, with white lime deposits ; most of the 

 sporangia are stalked (up to 3 mm. high), but some are 

 rosettes. 



On dead wood and decaying fungi. Peradeniya, Ganga- 

 ruwa, Edangoda. 



