134 A. E. HILTON ON 



the plasm simply settled down into rounded masses of spores and 

 capillitium, without surface nets or columellae. In other words, 

 they answered to Lister's description of Stemonitis fusca var. 

 confluens ; but the confluent condition was clearly accidental. 

 The spores were unaffected, and readily germinated in water. 



During the four months under review, the most frequent appear- 

 ances were those of Lamproderma columbinum. They are first 

 visible as small, watery-white, semi-translucent globules, more or 

 less clustered into little groups. The plasm then secretes stalks 

 and columellae, and forms vertical cylindrical sporangia, 1/8 of 

 an inch high, which after turning pinkish, reddish brown, and 

 then black, dry ofE to a bronze-like or brassy lustre, the process 

 occupying two or three days. 



Attempts which I have made to trace the plasmodia of this 

 species within the interstices of the wood have failed. The 

 interior of fragments taken from the log while sporangia were 

 rising presented only a wet appearance, indistinguishable from 

 ordinary moisture ; and when pressed out on to a glass slip, and 

 placed under the microscope, the fluid merely exhibited a mis- 

 cellaneous gathering of fungoid and bacterial bodies, together 

 with other elements which were possibly ingredients of plasmodia. 

 It is probable that while within the wood the plasm is watery- 

 clear, and the plasmodium so ill-defined that it only becomes 

 distinguishable on emerging to the surface. 



One patch of Lamproderma which appeared in July was about 

 eight inches long ; and another patch, two months later, covered 

 twenty square inches ; but for the most part, the groups were 

 small and very scattered, suggesting independent developments 

 of small and separate plasmodia rather than those of larger 

 plasmodia, maturing in various parts at different times. 



The four little groups of Physarum nutans which appeared on 

 the log, one at the end of July and the others a month later, were 

 first discernible as minute masses of plasm of a dull yellow colour 

 speckled with lime granules. Under the microscope, with 1/2 inch 

 objective, a wrinkled and iridescent membrane could be seen 

 between the lime clusters ; but as development proceeded, the 

 lime at the surface increased until the sporangia were completely 

 covered with a frail calcareous crust. 



Coming now to generalities, my daily records show that during 

 these four months of activity, from the end of May to the begin- 



