DESCRIPTION OF PLATES. 



PLATE 1. Frontispiece. Cranberry scald, showing different stages in the prog- 

 ress of the disease. A. Early stage. B. Later stage, showing dark zones. 

 C. Berry completely destroyed. 



PLATE II. Fig. 1. A cranberry leaf, showing pycnidia of Guignardia vaccinii 

 thickly scattered over the under surface ; a, a cranberry blossom blasted by 

 Guignardia vaccinii, showing pycnidia on calyx, corolla, and pedicel; 7>, a 

 blasted fruit, showing pycnidia. Fig. 2. A vertical section of a single pyc- 

 nidium of Guignardia vaccinii from a cranberry leaf, showing pycnospores 

 in various stages of development. Fig. 3. An immature pycnospore of 

 the same fungus, showing the partially foruied appendage ; a, the same, 

 showing a little later stage of development ; It and c, fully developed pyc- 

 nospores and appendages. Figs. 4, 5, 6, 7, 8, and 9. Various stages in the 

 germination and growth of pycnospores of Guignardia vaccinii grown in 

 weak sugar solution ; 4, 5, 6, and 7, seventy-two hours after sowing; 8 and 0, 

 eighty-six hours after sowing. Fig. 10. A vertical section of a perithecium 

 of Guignardia vaccinii, showing asci, from a cranberry leaf collected in New 

 Jersey. Fig. 11. Three asci, with ascospores showing variations in length 

 of the stipe and the arrangement of the spores ; a and &, from perithecia on 

 a leaf ; c, from a pure culture. Fig. 12. A fresh, mature ascospore, show- 

 ing the usual condition, in which the protoplasm is very coarsely granular. 

 Fig. 13. An old ascospore from a dried specimen, having its contents homo- 

 geneous. Fig. 14. a, A portion of the coarse brown mycelium from the 

 interior of a scalded berry, from which a culture was made December 23, 

 producing pycnidia and ascogenous perithecia of Gmgnardia vaccinii ; 1), a 

 portion of younger, lighter colored hypha? from the same berry. Fig. 15. 

 Pestalozzia gncpini vaccinii ; a, a conidium having an apical appendage with 

 three branches ; fr, a conidium having an apical appendage with four 

 branches ; o, a germinating conidium ; d, a germinating conidium sending 

 out two germ tubes. 



PLATE III. Fig. 1. Vertical section through an acervulus of Glomcrella rufo- 

 maciilans vaccinii from the under surface of a cranberry leaf. Fig. 2. 

 Four conidia from the same, showing some of the variations in form and size. 

 Fig. 3. A portion of an acervulus of Glomerella rufomaeulans vaccinii from 

 a pure culture on corn meal, showing the dark-colored seta? which are occa- 

 sionally found; a and &, conidiophores and conidia from another pure cul- 

 ture on corn meal. The conidiophores arise from a dark stromatic layer 

 consisting of cells resembling appressoria, as shown in 3, a. No large acer- 

 vuli, forming dense masses, occurred in this culture. Fig. 4. Appressoria 

 or chlamydospores from pulp of a cranberry from Massachusetts destroyed 

 by Glomcrella rufomaeulans vaccinii. Fig. 5. Portion of mycelium from 

 corn-meal culture No. 736, forty-two days old. Conidia and appressoria 

 found, fifteenth day ; matured asci appeared the twenty-third day no light 

 spots seen in these. Where they appear they are probably due to the presence 

 of vaeuoles or oil globules. Fig. 6. An ascogenous perithecium of the same 



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