BY R. GREIG SMITH. 459 



hyphca. The spherical cells behave as conidia or as any cell of 

 the hyphte, for when isolated and inserted in nutrient media they 

 germinate in a normal fashion (PI. xiv., fig. 10). The aerial 

 hyphae may produce the dark-coloured, thick-walled, spherical 

 cells (asci), but this is exceptional. It was observed in the case 

 of white hyphfe growing on sterile sugar-cane. 



I cannot identify the mould with any hitherto described fungus, 

 but that may be due to the fact that allied microscopic fungi 

 are classified by means of the perithecia or pycnidia which are 

 formed when the mould breaks through the epidermis of the host 

 plant. This stage I have not seen. But as I have given other 

 details, the mould will, I think, be recognised by future workers. 



EXPLANATION OF PLATES XIIL-XV. 



Plate xiii. 



Figs. 1-2. — Development of the dark-coloiwed cells in hanging drop of 



ordinary nutrient bouillon {x 425). 

 Fig. 3. — Perithecia in outline on sterile sugar-cane ( x 80). 

 Fig. 4. — Spores from a ruptured peritheciam ( x 425). 

 Fig. 5. — Spores germinating ( x 425). 



Fig. 6.— Chain of dark-coloured cells imbedded in starch-paste ( x 500). 

 Fig. 7. — Cells from a ruptured immature perithecium ( x 500). 



Plate xiv. 



Fig. 8.— Growth on the surface of levulose-asparagine-gelatine. Diagram- 

 matic ( X 2). 

 Eig. 9. — Flask-shaped terminal cells of aerial hyphae ( x 425). 

 Fig. 10. — Isolated terminal cell germinating { x 425). 

 Fig. 11. — Intergrowth by penultimate cells ( x 425). 



Plate xv. 



Fig. 12. — Red gum in large vessel of vascular string. Section of fresh cane 



( x 75). 

 Fig. 1.3. — Formation of perithecia. Film from starch-paste ( x 400). 

 Eig.l4. — Section of potato culture showing goblet cells of perithecial wall 



(x400). 

 Fig. 15. — Section adjoining the same, showing absorption of wall and fusion 



of perithecia ( x 400). 



