LISTER : THE HAUNTS OF THE MYCETOZOA. 
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chaena corlicalis occurs so frequently on dead poplars that 
among the many specific names it has received is that of 
populina. On lichened trunks of living poplars, the Rev. 
William Cran has found in Aberdeenshire small forms of Mar¬ 
garita. metallica and Dianema corticatum, besides other species. 
Arboreal Mycetozoa.— Before leaving the subject of living 
trees as a haunt for Mycetozoa, I should like to draw particular 
attention to this “ arboreal habitat ” (as it may be called) 
as one of which we have still much to learn. Two observers 
only, that I know of, have systematically examined the 
trunks of living trees with much success—the Rev. William. 
Cran, in Aberdeenshire, and Mr. Kumagusu Minakata, in 
Japan. Both gentlemen are blessed with exceptionally 
keen eyesight. I have had the privilege of being shown 
some of his hunting grounds by Mr. Cran. Instead of 
the sheltered woodland one is accustomed to regard as the 
favoured haunt of Mycetozoa, I was taken to a bare 
open country, divided into pasture and cornland by rough 
granite walls, with here and there scattered homesteads, sheltered 
from the weather b}/ groups of trees. It was on these trees, as 
well as on others even more exposed, that Mr. Cran pointed out 
wonderful growths of Orcadella operculata, and scattered patches 
of Badhamia affinis, B. versicolor, and Diderma arborenm, species 
which I had never seen growing before, nestling amongst moss 
and lichens, at a height of five feet and more from the ground. 
Many of the rare arboreal species, which have hitherto been found 
in Scotland by Mr. Cran alone (for I saw only what he showed 
me), have also been obtained in similar situations by Mr. Minakata 
in Japan. Whether the moist climate of Aberdeenshire is 
especially favourable to the growth of Mycetozoa living in such 
exposed situations, or whether Mr. Cran’s success is due to 
his superior powers of observation, I cannot say ; but I confess 
that, after this lesson, I came south determined to search the 
trunks of living trees, and, up to the present time, my efforts, 
though not entirely fruitless, have yielded but small results. 
A list of the arboreal Mycetozoa that we know of (thirty-six 
species in all) will be found at the end of this paper ; in it are 
included those on living wood only, and not species growing 
on dead limbs of living trees. 
Dead Leaves.— Turning now to the species occurring on 
