DESCRIPTION OF PLATES. 



Plate 1. — Frontispiece. Cranberry soald, sbowiiit; different stages in the prog- 

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

 C. — Berry completely destroyed. 



Plate IL — Fig. 1. — A cranberry leaf, showing pycnidia of Gtiigiiardia raccinii 

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

 Guignardia vaccina, showing pycnidia on calyx, corolla, and pedicel ; li. a 

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

 nidium of Guignardia raccinii from a cranberry leaf, showing pycnospores 

 in various stages of development. Fig. o. — An immature pycnospore of 

 the same fungus, showing the partially formed appendage ; a. the same, 

 showing a little later stage of development ; h and r. fully developed i)yc- 

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

 germination and growth of pycnospores of Guignardia raccinii grown in 

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

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

 of Guignardia raccinii, 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 arrangemeyt of the spores; a and J>. from perithecia on 

 a leaf; c. fi-om 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 Immo- 

 geneoiis. Fig. 14. — a, A portion of the coarse brown mycelimn from the 

 interior of a scalded berry, from which a culture was made December 2:'., 

 producing pycnidia and ascogenous ])erithecia of Guignardia vaccinii : b, a 

 portion of younger. lighter colored hypha" from the same berry. Fig. 15. — 

 Pestalozzia guepini vaccinii : a. a conidium having an apical appendage with 

 three branches ; h. a conidium having an apical apiiendage with four 

 • branches ; c, a germinating conidium ; d, a germinating conidium sending 

 out two germ tubes. 



Plate III. — Fig. 1. — Vertical section through an acei'vulus of Glnmcrella rufo- 

 maculans faccinii 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. n. — A portion of an acervuliis of Glomcrella rufoniaculans vaccinii from 

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

 sionally found ; a and h, 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 rufoniaculans vaccinii. Fig. 5. — Portion of mycelium from 

 corn-meal culture No. 730, 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 vacuoles or oil globules. Fig. 6. — An ascogenous perithecium of the same 



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