THIELAVIOPSIS PARADOX A. 533 



branches, perpendicular to the main hypha, 20-80 ^ long and 

 4 jx in diameter. Like the raicroconidiophores, they are cut 

 off by a septum just above the point of origin, and the longer 

 of them may have one or two additional septa, rather close 

 together, above this. At first they are slightly clavate and 

 filled with finely granular protoplasm. 



When the conidiophore is mature, the apex dissolves, and 

 some of the protoplasm is extruded. In general the extruded 

 mass assumes an oval shape, but sometimes it becomes 

 spherical. A wall is then formed round it, with a flat septum, 

 cutting it off from the remaining protoplasm, at the apex of 

 the conidiophore. At first the contents of the spore are finely 

 granular, but they soon become vacuolated, and the spore 

 increases in size. Meanwhile another portion of the proto- 

 plasm witliin the conidiophore is seen to divide off, and is 

 gradually pushed out : as it emerges it is more or less pyriform, 

 but when completely extruded it becomes oval and proceeds 

 to form a cell waU, &c., exactly in the manner of the first. 

 I have never been able to detect any division of the protoplasm 

 before the extrusion of the first spore mass, but all succeeding 

 spore masses are clearly cut off, one at a time, within the tube. 

 This process is continued until a chain of spores, usually 

 about a dozen, is produced. The conidiophore is then highly 

 vacuolated, and subsequently appears empty. The spores are 

 generally united, end to end, but sometimes a chain is divided 

 into two or three separate portions. The spores increase in 

 size after their formation, but the terminal one is always the 

 largest. Short conidiophores, which form only one conidium, 

 are not uncommon, and any number from tliis to twenty may 

 be produced. 



The production of macroconidia is a much slower process 

 than that of the microconidia. On the average, one micro - 

 conidium is extruded in from forty-five to sixty minutes. 

 They begin to darken about three hours after extrusion ; the 

 chain of macroconidia therefore exhibits dark spores at the 

 apex and hyahne spores at the base during the period of 

 formation. At first the spores decrease in size from the apex 

 to the base of the chain, but subsequently all but the apical 

 spore attain practically tlie same dimensions. 



6(11)10 (69) 



