38 Howard,—On a Disease of Tradescantia. 
Fig. 15. Portion of a mycelium as found growing on the epidermis under 
Fig. 16. Low power view of Cladosporium ( Hormodendron form) with conidio- 
phores to show habit. 
Fig. 17. One of the conidiophores of last, more highly magnified and showing 
apparent dichotomous branching. 
Fig. 18. Germination of spore of Cladosporium in a hanging-drop (made Aug. 25 
at 9 p.m.) at 10.30 p.m. Aug. 26. t- 22.5 0 C. 
Fig. 19. The same next day, Aug. 27, at 11.30 a.m. t = 22*5° C. 
Fig. 20. The same at 3.30 p.m. under low power. At 6.15 p.m. aerial hyphae 
were emerging from the drop to form conidiophores. 
Fig. 21. Stages in the development of one of the above conidiophores. <z = at 
6.15 p.m. Aug. 28, /=23°C. ; £ = at 10.30 p.m., t- 2 2°C., several minute gas- 
bubbles have appeared on the elongated hyphae; c = at 12 p.m., t= 2 2°C., the tip 
has grown forwards and been cut off by a septum ; d — at 12.20 a.m., t= 2i°C., 
the terminal segment is budding out another segment at its apex; £=12.35 
^ — 21°C., another bud appears below the first septum (x). 
This point ( X) is marked as a fixed point throughout, f, the last-named bud is 
now (12.55 a -nn., /=22°C.) budding at its apex, and minute gas-bubbles appear 
at the surface of the older buds ; ^=at 1.10 a.m., /=23.5°C. [N.B. The rise in 
temperature was due to the heat radiated from the lamp.] k = at 9.30 a.m., 
*=21.5° C. 
The conidiophore is now complete, and any segment acts as a spore. At the * 
is another branch, the fate of which was further followed. z=this branch at 
9.45 a.m., *=21.5. The large gas-bubble at the right hand grows larger. £ = at 
3.15 p.m., /= 21.5. All under •§■. 
Fig. 22. Stages in growth of a branch from a mycelium twenty-four hours old 
in hanging-drop, a, at 9.30 a.m., Aug. 27, ^ = 2i°C.; b, at noon same day, 
22-5. The vacuolation, beginning in a, is now more pronounced, and several septa 
have formed. c = at 2.45 p.m., l=22^°C. ; d, the distal moiety of same at 4 p.m., 
^=23; e, at 5.45 p.m., £ = 22*5. Next day the walls begin to thicken and turn 
brown, and in a day or two the short swollen segments (as in Fig. 13) pre¬ 
dominate. 
Fig. 23. Portion of epidermis, seen from within, showing penetration of infecting 
hypha. The part in paler outline is the germinating spore on the outside : the 
portions inside are running in the middle lamella. 
