Larch and 



Spruce Canker. 



187 



Description of the Figures. 

 Plate t. 



Fig. 1. Portion of stem of a young larch, showing a small 

 canker wound with ascophores or cups of Dasyscypha calycina. 

 Nat. size. (The result of artificial inoculation.) 



Fig. 2. A small but characteristic canker, with ascophores and 

 conidia-pustules of D. calycina. Nat. size. 



Fig. 3. Ascophores and conidia-pustules of D. calycina 

 x 35- 



Fig. 4. Ascophores and conidia-pustules of Dasyscypha 

 resin aria, x 35. 



Fig.. 5. Portion of a larch branch showing the white flocculent 

 tuft with a central drop of sap, which is constantly located near 

 to a " foundress " aphis when with her eggs, x 5. 



Plate II, 



Fig. 1. Section through an ascophore of Dasyscypha calycina, 

 x 40. 



Fig. 2. Asci containing spores, also paraphyses, of D. calycina, 

 x 400. 



Fig. 3. Section through an ascophore of D. calycina, showing 

 the mycelium of the fungus permeating and rupturing the bark 

 and cortex, x 400. 



Fig. 4. Section through a conidial-pustule of D. calycina, 

 x 50. 



Fig, 5. Conidiophores and conidia of D. calycina, x 1,200. 



Fig. 6. Conidia of D. calycina germinating in contact with a 

 thin section of larch bark in a hanging-drop, x 1200. 



Fig. 7. Ascophores of D. calycina germinating in contact with 

 a thin section of larch bark in a hanging-drop, x 400. 



Fig. 8. A single spore of D. calycina germinating ; the germ- 

 tube has penetrated the wall of the cell through a bordered pit, 

 x 400. 



Fig. 9. Ascus containing spores, also paraphyses, of D. calycina, 

 var. Trevelyani, Cooke. A variety distinguished by the spores 

 being larger than in the type form, x 400. 



Fig. 10. Section through ascophore of Dasyscypha resinaria, 

 x 40. 



