ELISHA MITCHELL SCIENTIFIC SOCIETY. 37 



fascicles, or tufts, of conidiophores arise from a more or less 

 compact fungus body termed a slrorna. This is formed at 

 various points on the vegetive mycelium within the leaf 

 tissue by a lateral growth of certain of the cells together 

 with a conjunction of cells of adjacent threads. In C. 

 Boehmci'icE Pk. this consists of a prominent globose body; 

 from this there are different degrees of compactness and 

 rotundity down to a few closely associated cells which bear 

 only a few conidiophores. 



The conidiophores themselves vary greatly in length, 

 size, general direction, markings and color. They may be 

 continuous, septate, geniculate, flexuous, toothed, or cylin- 

 drical. The geniculations, the denticulation and much of 

 the flexuous condition is brought about by the manner of 

 growth of the conidiophore while it is bearing conidia. In 

 nearly all the species the conidia are, as termed in some 

 cases, lateral and acrogenous in their production on the 

 conidiophores; /. <?., they are borne both laterally and termi- 

 nally. This is not, strictly speaking, true, but only 

 appears so to be after several conidia have been produced 

 from a single conidiophore. Probably all of the conidia 

 are primarily acrogenous and only later appear to be lateral 

 after the conidiophore has grown at one side beyond the 

 apex on which the cojiidium was developed. If the 

 conidiophore is growing very rapidly the new growth, 

 which pushes out at one side of the apex on which the 

 conidium is situated, will extend to a considerable distance 

 before another conidium is borne at the new apex. This 

 again grows out past the new conidium, and so on. If the 

 new growth of the conidiophore has been quite divergent 

 from its primary direction a geniculation, or abrupt bend, 

 will appear at the point where the conidium was attached. 

 After the second conidium is borne the conidiophore will 

 usually diverge in a different or opposite direction, giving 

 a somewhat zigzag appearance. At each one of these 



