154 



MORPHOLOGY. 



lular passages, and grows as a little stem from the stomate, branching 

 externally in a tree-like form. I observed it in all its stages of develop- 

 ment from the germ. At the points of the branches, and distinctly en- 

 closed by the membrane, a small cell is seen, which gradually swells to a 

 considerable size, and then separates itself from the branch with the in- 

 tegument it has derived from the parent cell. This is the mode of forma- 

 tion of the spore. According to Meyen's delineations*, the same pro- 

 cess goes on in Penicillium. I found upon damp linen a colourless mould 

 (Mucor ?) (fig. 123.), consisting of one cylindrical cell (seldom more), 

 much ramified upon the surface ; it had one stem, the end of which was 



123 



spherically enlarged, and furnished with small pear-shaped processes, 

 projecting in all directions. An individual cell was distinctly visible in 

 the interior and at the point of each process, which, gradually enlarging, 

 separated itself from its support. On the withering leaves of the Passi- 

 flora alata, I found a mould that was almost as black as pitch, consist- 

 ing of one simple thread, formed below of shorter and thicker, and 

 above of longer and narrower cells, of which the uppermost, which was 

 spherically expanded, exhibited the same process of spore- development. 

 I found upon the withered stalks of the same plant another whitish-gray 

 mould, composed of short and thick cells at the bottom, and longer and 

 thinner ones at the top, forming ramified threads. The two or three last 

 joints of the stalks and the branches contained a turbid, mucous, granu- 

 lar fluid, which sometimes exhibited very small but sharply-defined 

 globules, or discs (cytoblasts). Very minute delicate cells were fre- 

 quently to be observed, closely applied upon the wall of the cell, 

 which was often arched outward over the cells. I met with all 

 possible stages of transition from this condition to a longer wart -like 

 projection of the wall, at the point of which lay a young cell, free and 



* Pflanzenphysiologie, vol. iii. pi. x. figs. 22. 20, and 21. 



losum. A section of the latter is given. P, A portion of the fungus, with spores in 

 different conditions of development (a d), and a barren branch (e). 



lk3 Mucor (sphcerocephalits ?). a, The whole plant, b, The head of the spore-case, 

 in a longitudinal section, the greater part of the processes with the spores being omitted 

 in the delineation, c, Earlier condition of such a protuberance, with the spore originat- 

 ing from it. d, Protuberance, with the ripe spore. 



