THIELAVIOPSIS PARADOXA. 529 



examinations, in a damp chamber. I have been able to keep 

 them under the microscope for tlu-ee hours continuously by 

 occasionally moistening the blotting paper. 



When mature, the conidiophore is hyahne or grayish, and is 

 filled with finely granular protoplasm. It remains quiescent 

 for some time after it has reached its full exteiLsion, and then 

 begins to extrude spores from the apex. A cell wall is developed 

 round the protoplasm in the apex of the tube ; at a distance 

 of about 10 a beliind the tip, the protoplasm becomes slightly 

 constricted, as is evident from tlie minute V-shaped depression 

 which is visible on each side witliin the tube in oi^tical section ; 

 a cross septum next appears as a dark line at this level, and 

 the terminal mass of protoplasm thus completes its cell wall ; 

 the apex of the tube is then dissolved, and the spore is slowly 

 extruded by the expansion of the protoplasm behind it. The 

 apex of the conidiophore as a rule is not inflated ; sometimes 

 it is slightly swollen, and then the spore first extruded is 

 somewhat capitate, but the swelling in the most pronounced 

 cases is only shght. In general, the microconidia, when first 

 extruded, are almost exactly rectangular in outline. 



By the time the proximal end of the first conidium has 

 reached the apex of the tube, another septum appears in tlie 

 tube at the same distance from the apex as before, thus 

 completing a second spore, which follows the first out of the 

 tube without any resting period ; and this process is continued 

 until as many as eighty spores have been extruded. The 

 spores issue in a steady continuous stream, each pressing 

 close on the previous one. It is evident that when the cross 

 septum appears in the tube, two terminal spore walls are 

 formed, one of which completes the spore wall of the upper 

 spore while the other begins the wall of the lower. At first, 

 during the extrusion of the first twenty or thirty spores, the 

 cross septum appears always at the same distance from the 

 apex : there is therefore never more than one spore within the 

 tube, and that is just about to be extruded. In the later 

 stages, however, the formation of spores is more rapid than 

 the process of extrusion, and it is possible to find two or three 

 completed spores within the tube in addition to the one which 

 is being pushed out. In the final stages, the process appears 



