Slugs as Mycophagists. A. H. R. Buller. 279 
bodies of Boletus scaber quietly feeding. No other slug could be 
seen anywhere. The next morning | detected the slime-trail of 
the slug in the neighbourhood of the heap of Boleti but nowhere 
else, the trail having been weakened or destroyed by dew 
formation; and the slug had disappeared. In all probability 
the slug had returned to the border whence it had originally 
come. 
Experiment VI. The next evening, September 11, I set out 
upon the gravel the same three heaps of fruit-bodies as had been 
used the night before. Again the heaps were made in a row 
parallel to the edge of the border, the intervals between the 
heaps being 4 ft., the Boletus scaber heap occupying the central 
position in the row and the Cortinarius caninus and Russula 
nigricans heaps the end positions. However, the arrangement 
of the heaps differed from that of the night before in that each 
heap instead of being only 12 ft. from the edge of the border was 
now 20 ft. The condition of the Russula migricans and Cor- 
tinarius caninus fruit-bodies was still. good, but the Boletus 
scaber fruit-bodies were now in an advanced stage of putrescence. 
The evil state of the Boletus scaber fruit-bodies was perhaps the 
reason why, as we shall see in the sequel, they were not visited 
by a slug in this particular experiment. The night was again 
very dark and still. At 9.40 p.m., with the help of a lighted 
taper, I found a Limax maximus which had just emerged from 
its hiding place and which was moving behind a block of sand- 
stone in the border 21 ft. from the fungi. At 11 p.m. I went 
out again and found that the slug had already travelled rr ft. 
upon the gravel toward the fungi from which it was now only 
g ft. distant. I watched the slug for a little time but, being 
afraid of disturbing it too much, soon retired into the house. 
At 12 p.m. I sought the slug again and found it 6°5 ft. away 
from the row of fungi; but, to my surprise, it was moving away 
from the row of fungi instead of toward it. At 1 a.m., the slug 
was 5 ft. away from each of the heaps of Boletus scaber and of 
Russula nigricans; at 1.30a.m., about 2 ft. away; and, finally, 
at 2a.m., actually upon one of the fruit-bodies of Russula 
nigricans devouring the gills. Thus the slug, after some five 
hours of wandering, had at last succeeded in finding one of the 
heaps of fungi set 20 ft. from the edge of the border where the 
slug had first been seen. 
The slug, between 9.40 p.m. and 11 p.m., must have travelled 
almost directly toward the fungi; for, during this period, it 
traversed 1 ft. of border and 11 ft. of gravel in the direct line 
of its journey. But between Ir p.m. and 1 a.m. this rapid pro- 
gress was not kept up and there was a great waste of time, for 
during this period the net advance of the slug toward the fungi 
