11 
DESCRIPTION OF PLATES. 
Plate I, Ceratocystis fimbriata, Ell. & Hals. 
Fig. 1. Sweet Potato showing blackened area, inhabited by the parasite. 
2. Cross section of the same. 
Plate II, Ceratocystis fimbriata, Ell. & Hals. 
Fig. 1. Sporophore of hyaline conidia figured 1 p. m. la, the same figured 1:50 p. 
m. 16, the same at 2:15 p. m. X 550. From test-tube cultures of sweet 
potato agar-agar. 
2. Group of hyaline conidia, showing variations in form from test-tube culture. 
2a, the same from plate culture X 400. 
3. Group of hyaline conidia sporophores, showing spore formation X 300. From 
test-tube cultures. 
4. Germinating hyaline conidia from cultures 24-48 hours old in sweet potato 
agar. 4a, young germ hypha with hyaline conidium forming. 46, hyaline 
conidium lately expelled from sporophore. 4c, commencement of sporo¬ 
phore or branch of hypha of germination X 550. 
5. Sporophores with olive conidia issuing from tips. 5a, characteristic primary 
spore first formed X 550. 
6. Sporophore of olive conidium greatly enlarged X 1,500. a, ruptured outer wall 
of sporophore. 6, protoplasmic contents of mother cell. 
7. Olive conidia germinating X 550. 
8. Successive stages in formation of olive conidia. 8a, sporophore aud spore 
figured 12:15 p. m. 86, same2 p. in. 8c, same 4:35 p. m. Sd, same 6:25 p. 
m. 8c, 9 a. m. 
9. Primary growth of mycelial hyphm from hyaline conidium. 
Plate III, Ceratocystis fimbriata, Ell. & Hals. 
Fig. 1. Mature pycnidium X 200. la, gelatinous mass of exuded spores. 
2. Fimbriate tip of beak or ostiolium X 500. 
3. Cross section of pycnidium showing large thin walled cells, previous to spore 
formation X 300. 
4. Gelatinous mass of pycnospores X 550. 4a isolated spores shortly after im¬ 
mersion in iodine. 46 pycnospore after 48 hours in sweet potato agar cul¬ 
ture. N, nucleus; G, ring of gelatinous granules. 
5. Cross section of pycnidium beak near base X 550. 
6. Primary growth of mycelial hyphaj from pycnospore X 200. 
7. Anastomosiug hyphse abundant on mycelium from pycnospores and hyaline 
conidia X 440. 
8. Germinating pycnospores. 8a ring of gelatinous uniting substance. 86 pro¬ 
mycelium in form of a sporophore with hyaline conidium issuing X 550. 
9. Primary stage in development of pycnidium X 550. 
10. Early stage in development of pycnidium X 550. 
11. Immature pycnidium X 400. 
