EXPLANATION OF PLATES. 109 



figure 35. Fig. 37.— An ascus 83 p long, from same cultures as figures 35 and 36. 

 Fig. 38. — An ascus 77 p long, from same culture as figures 35, 36, and 37. Fig. 39.— 

 An ascus 55 p long, from corn-meal agar slant culture from apple leaves from 

 Winchester, Va. — Figs. 40 to 44. — Glomerella cingulata from fig. Fig. 40.— An 

 ascus 110 p long, from corn-meal agar slant culture 1283d, from conidia on fruit 

 from Norfolk, Va. Fig. 41. — An ascus 92.5 p long, from same culture as figure 40. 

 Fig. 42. — An ascus 85.5 p long, from corn-meal agar slant 1283a, from same source 

 as 1283d. Fig. 43.— An ascus 63.5 p long, from corn-meal agar slant 1283e, from 

 same source as 1283a. Fig. 44. — An ascus 56 p long, from same culture as figure 43. 



Plate IV. Pomelo leaves showing development in moist chamber of numerous colonies 

 of Glomerella cingulata on apparently healthy leaves for 9 days. The lower leaf 

 1 year younger than the upper. The colonies originated chiefly from the midrib. 



Plate V. Glomerella cingulata on pomelo leaves. Figure 1 shows development of 

 numerous scattered colonies on apparently healthy leaves in moist chamber, evi- 

 dently rising from separate points of infection. Figure 2 shows small leaf 1 year 

 younger taken from the same plant and treated in the same manner. No fungus 

 developed, as the leaf was apparently not infected. 



Plate VI. Glomerella cingulata on 2 orange leaves, showing the development of the 

 fungus on apparently healthy leaves in a moist chamber and the localization of 

 the colonies which evidently originated from separate points of infection. The 

 rubber plant leaf at the right shows the development of the fungus from the petiole 

 along the midrib. Acervuli first developed on the petiole, which has been 

 removed. 



Plate VII. Glomerella lindemuthianum from bean. Six corn-meal agar cultures started 

 from conidia from a single acervulus, showing the uniform character of cultures 

 of this species and the characteristic dark mycelium usually producing acervuli 

 only. 



Plate VIII. Glomerella cingulata from Persea. Ascospore generation 2, tube a, show- 

 ing separate perithecia thickly covering the surface of the medium. Conidial 

 generation 13, tubes b and c, showing chiefly acervuli. Conidial generation 14, 

 tubes b and c, originated from generation 13, b and c, respectively, are strikingly 

 different. Of generation 14, b shows chiefly acervuli and conidia and c chiefly 

 perithecia, which are arranged in masses along the line where the spores were 

 planted. 



Plate IX. Glomerella cingulata from Persea. Conidial generation 9, tube a, shows 

 numerous scattered perithecia and a few acervuli near the bottom. Conidial 

 generation 16, tubes b and c, from which conidial generation 17, tubes b and c, 

 were made, produced almost entirely acervuli. Of generation 17, tube b produced 

 almost entirely perithecia, while c was practically identical with generation 16, 

 tube c, showing chiefly acervuli. 



Plate X. Glomerella cingulata from Persea. Conidial generation 17 produced from 16, 

 tube b, which was almost identical with tube 4. These cultures showed rather 

 regular intergradations from tube 1, which chiefly produced perithecia, to tube 7, 

 which produced acervuli almost entirely. Tubes all the same age. 



Plate XI. Glomerella cingulata from Persea. Conidial generation 17, tube b, showing 

 mostly perithecia, and six subcultures from the same. All the cultures except 

 the one at the extreme right showed a great predominance of acervuli, with but 

 few perithecia, showing a reversion to the form in generation' 16, tube b. 



Plate XII. Glomerella cingulata from Persea. Showing striking variations. Conidial 

 generation 17. Tubes d, e, /, and g, all originated from generation 16, tube b. 

 Compare Plate IX. Of generation 17, tubes d, e, and/ show mostly perithecia; 

 g has perithecia at the bottom of the culture and acervuli above. Of conidial gen- 

 eration 19, tube b shows mostly acervuli, while of generation 20, tube b produced 

 mostly perithecia. 

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