XIII.] 



ABOUT FUNGI. 



183 



FIG. 135. 



to end. At its summit it bears a string of round 

 cells which, when separated from the plant, cannot 

 be distinguished from Torula. These are the spores 

 or conidia, which, if sown on an 

 appropriate substance, send out 

 shoots from various parts of the 

 cell-wall. These shoots are at first 

 simple elevations of the cell-wall, 

 like the budding of Torula, but 

 they continue to elongate by trans- 

 verse division of the cells compos- 

 ing them until a considerable ex- 

 tent of surface is covered by their 

 ramifications. These shoots are 

 termed hyphcz, and the felt -like 

 mass formed by their growth is known as the myce- 

 lium. These hyphce send off branches above and 

 below ; those above, which are erect, are the aerial 

 hyplice, whilst those below are the submerged hyphce, 

 and serve the purpose of roots. The aerial hypha 

 bear upon their summits the conidia, which also are 

 formed by the transverse division of the cells. It 

 should be noted that, neither in this nor in any other 

 form of fungus, do cells multiply by longitudinal 

 division. 



Another form very similar to Penicillium is Mucor, 

 but in this the hypha consists of an undivided tube, 

 or a cell drawn out to a very great length. The 

 aeiial Jiyplicz bear a large globular cell (the sporan- 

 gium}, which contains a large number of smaller cells 

 (ascospores). These ascospores are set free by the 

 bursting of the sporangium (or ascus, as we shall 



