210 Fulton . — On the Dispersion of Fungi 
the hymenial surface is firm and solid, greenish-grey in colour, 
and emits a faint, mawkish, but sweetish and honey-like 
odour 1 , which is attractive to house-flies (Musca domes tic a). 
Very soon, however, and before the elongation of the stem is 
completed, it begins to darken, the odour becomes somewhat 
foetid, and the consistency changes, so that it gets rather 
sticky and tenacious. A little later it is dark green, almost 
black, the odour is very strong and repulsively foetid, and its 
consistency slimy or almost fluid. These changes in the 
physical character of the hymenial mass begin at the apex 
of the gleba, and rapidly extend downwards. They seem to 
depend largely upon the influence of light, for if one side be 
protected from its action the change in consistency and colour 
is retarded on that side. A specimen I kept in a darkened 
place only very partially liquefied and did not drop off, but 
dried up into a hard, black, shining, odourless mass. When 
examined microscopically the foetid fluid is seen to contain 
myriads of spores, each 0-03 mm. long. The rupture of the 
peridium and the changes I have described occur during the 
hot months of the year, from the early part of July till the 
end of September, and therefore at a time when insect life is 
very abundant, and when myriads of flies abound. As soon 
as the stercoraceous odour is developed, the liquefying hy- 
menium is visited by large numbers of flies, which sometimes, 
on hot sunny days, almost cover it, and suck up the fluid 
mass with great avidity, very soon removing the most of it. 
When the weather is dull and cloudy or cold fewer flies are 
to be seen on the glebae ; but it is possible that the deli- 
quescence then goes on more slowly. 
The fact that flies are attracted to the stinking slime of 
Phallus impudicus has been long known to botanists. The 
earliest notice I have found of this circumstance occurs in 
some Latin verses 2 composed by the old botanist Hadrianus 
1 It has been shown by Messrs. Rathay and Haas (op. cit. p. 43) that the 
liquefying hymenium contains three forms of sugar, laevulose, dextrose, and 
another, intermediate between dextrose and gum. 
2 Quoted by von Schlechtendal, Linnaea, Bd. xxxi, p. 147, 1862. 
