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ductive condition, tlie entire protoplasmic substance, plasmo- 
dium, becomes transformed into sporangia or larger receptacles. 
In JEthaliiwi septicum , the so-called “ flowers of tan,” tbis spore- 
receptacle is represented by a cake-like mass, not unfrequently 
measuring a foot in length and breadth and over an inch in 
thickness. The inside of the cake is dark-grey, easily pul- 
verized, and penetrated by yellow veins consisting of tubes 
interwoven in all directions. The skin, or cortex, consists of 
densely interwoven, irregular bundles of tubes connected in a 
peculiar manner, and containing an immense number of cal- 
careous grains as well as a yellow pigment. JEthalium, in its 
plasmodium condition, is able to creep away from the tan upon 
which it was originally growing, and, climbing up neighbouring 
plants to the height of several feet, accumulates upon their leaves. 
The monadiform germs developed from the spores are, under 
unfavourable circumstances, transformed into microcysts ; when 
dry they remain in this state for months, reverting again to the 
mobile form when placed in water. The young plasmodia are 
also capable, under like conditions, of forming cysts out of 
which they again creep on the return of warm, moist 
weather. The more matured plasmodia may likewise enter upon 
a temporary state of rest, — sclerotium. First drawing in its 
arms or outlying ramifications, it next assumes a sieve-like 
contour or becomes resolved into a mass of irregular nodules, 
and the whole substance breaks up into a large number of 
round or polyhedral cells. When placed in water, the cell- 
walls again become absorbed, and the sclerotium reverts to the 
condition of a mobile plasmodium. Finally, the plasmodium 
having attained its full growth, a fine membrane, or pellicle, 
is formed over its surface and the interlacing capillitium 
and spores within, the lime contained within the plasmo- 
dium being deposited in the form of granules on the capil- 
litium or wall of the sporangium. The passage to this 
reproductive phase is accomplished with great rapidity,— two 
hours only being quite sufficient, in the case of JEthalium, to 
convert a soft mobile plasmodium into the motionless, cake-like 
sporangium. The water previously contained in the plas- 
modium is partly expelled in the fluid state, while the residue 
speedily evaporates/ 
Upon the data included in the foregoing epitomization of 
the structure and life history of the Myxomycetes, and more 
especially with regard to those that relate to their earlier loco- 
motive and ingestive faculties, it is not to be wondered at that 
many biologists have come to look upon their association with 
vegetable organisms as no longer tenable, and to decide that 
their nearest allies are to be sought for among the animal series. 
Such an opinion was freely expressed by Prof. Allman in his 
