18 
agree with the descriptions which have been repeatedly given of it. It 
consists of a thick-walled mycelium tube, the lumen of w hich is not con¬ 
stant in diameter, but in some places widens out and in other places is 
almost or apparently quite closed. The thickness of the mycelium fila¬ 
ment also varies constantly. These coarse, tough threads are found 
in diffeient parts-of the stem, some at the center, others nearer to the 
periphery, running between the cells or into them, and with their sharp 
end pushing directly through the thickest walls, Fig. 24. 
In fruiting, the mycelium forms a great number of short slender 
branches. Great masses of these are found in little nests in the abnor¬ 
mal tissue, Fig. 20, also Fig. 8. They are more slender and delicate 
than the mycelium already described and are generally of quite irregu¬ 
lar form. Fig. 23 represents a much branched mycelium filament, which 
appeared in a break in a section. It appeared to have jmshed its way 
in between the cells and not to have penetrated them. The slender fila¬ 
ments of these masses swell up into a form like that represented in Fig. 
25, except that in many cases—indeed in most cases—the filaments lose 
their individual form and are more or less blended iu a gelatinous, 
shapeless mass. Founded places with little masses of rich protoplasm, 
Fig. 25 a , indicate spores in an early stage of formation. All stages 
may be found in the same mass. Fig. 2G shows later stages, where the 
ends of the filaments appear club shaped and within are seen the al¬ 
most ripe spores. The mature spore, Fig. 27, is one celled with two 
wall&; the outer thick, brown, and covered with spines. The inner 
delicate and transparent. 
From the comparatively small number of species in which abnormal 
changes under the influence of parasitic fungi have been carefully 
studied, it is hardly possible as yet to venture on any general or theo¬ 
retical statements concerning the pathological changes induced by 
such parasites. It seems best therefore, in the present instance, to 
simply recapitulate the injuries occasioned to the host by the fungus 
in question, since it is only by multiplied observations of the same kind 
that sufficient data can be gathered for a more general conception of 
the relations of parasite and host. 
The changes observed in the stem of Zece Mays are briefly as follows : 
An extraordinary hypertrophy of the parts of the host where spore 
formation takes place, the irregularity of which gives rise to peculiar 
and conspicuous distortion. 
Microscopic examination shows : (1) Great multiplication of cells near 
the periphery; (2) decrease iu thickness of cell walls and, in case of 
the bundles, of the size of the elements ; iu m’any cases a decrease in 
the size of the cells of the ground tissue also; (3) distortion of the 
stomata, particularly of the accessory cells, (4) a breaking up of the 
bundles and a changing of their elements, so that in many cases phloem 
can not be distinguished from xylem; (5) a marked increase of cell 
contents. 
