4 H. MARSHALL Vt'AIlD. 



spore-like bodies is suggested These spherical bodies are, 

 however, not solid, but cavities excavated, so to speak, in the 

 protoplasm, and filled with watery liquid. In the first place 

 they are not constant, but may be seen to change their position, 

 size, &c., very slowly ; moreover, they eventually disappear, not 

 by escaping bodily from the sac, but slowly, and this is accom- 

 panied by other changes. On crushing the whole carefully, these 

 spheres are no longer seen in the extruded mass of protoplasm. 

 Staining reagents do not colour them darker than the matrix, 

 and they are not rendered clearer by such fluids as would cause 

 contraction of denser protoplasm ; on the contrary, solutions of 

 sugar, salt, &c., and such reagents as iodine, glycerine, &c., 

 make them disappear, evidently by the abstraction of water. 



With careful treatment I have caused these vacuoles to reap- 

 pear, after applying weak sugar solution, on washing in pure 

 water. "What is the nature of this vacuolisation ? How far is it 

 normal, and how far connected with other phenomena, must be 

 left for future consideration. The proofs that these bodies 

 are vacuoles must, however, I think, be admitted. 



The strongest evidence that the papillate body is itself a spore, 

 however, and the basis on which I have chiefly proceeded, is aff'orded 

 by its germination. This occurs in pure water on glass typically as 

 follows. At about two to five, frequently three nearly equidistant 

 spots, the exospore becomes thinner, and pushed aside by the 

 swelling endospore, and a delicate finger-like tube is protruded 

 from each (fig. 8). This tube has very thin cellulose walls and a 

 blunt, rounded apex. It may dilate slightly just beyond the place 

 of exit, and the constriction at that spot is rendered conspicuous 

 in contrast; otherwise the diameter of the tube is equals and 

 measures about one fifth of the narrow diameter of the spore 

 (fig. 9). This germinal tube rapidly grows forwards, extending, 

 by apical growth, as a simple unbranched cylinder for some 

 time. As it elongates its diameter remains uniform, and 

 its cavity continuous with that of the spore. The orange- 

 coloured granular spore-contents meanwhile pass along the 

 germinal tube, often presenting a most beautiful streaming 

 motion here and there along their course ; vacuoles and oil drops 

 form both in spore and tube, and branches are soon put forth at 

 various points, to remain short or become extended, in the same 

 manner as before (fig. 9). This process is, however, limited, 

 and the amount of growth is clearly dependent upon the quantity 

 of food material originally present in the spore.^ 



^ Attempts to grow a more extensive mycelium in nutritive fluids of 

 various kinds have utterly failed ; this is not surprising in the light of what 

 follows. 



