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SECTION. OF VEGETABLE PATHOLOGY. = «893 
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any difference in the quantity or quality of the crop. © If, however, | 
- it attacks very young leaves it may be harmful and some treatment z 
be necessary. Repeated applications of sulphur, made when the 
- ~ shoots are 3 to 5 inches long, will check the multplication of the 
- - Phytoptus. Washing the vines after they are pruned inearly sprmg. - 
’ with boiling water will destroy the eggs and larve concealed within 
the bud scales and crevices of the bark. 2 
——- ; F. LaMson SCRIBNER. > 
-  _ Hon. Norman J. Corman, Commissioner. eae 
Bs EXPLANATION OF PLATES. 
ay Puate I. 
ee STRAWBERRY-LEAF BLIGHT (SPH2ERELLA FRAGARLIA). 
_. Fic.a. Diseased leaf, natural size, attacked by the summer stage of the fungus. 
aie (G.M., pinx.) 
- Fie.b. Tuft of conidiophores and conidia which have broken through the upper 
epidermis. (E.A.S., del.) ; 
. Fic.ec. Conidia more highly magnified; three of them have sent out germ fila- “ 
ments. (H. A. S., del.) +: 
Fic. d. Perithecium bearing conidiophores around the ostiohiam. (E.A.S8., del.) 
Fic.e. Section of perithecium, showing asci within. The asci are borne upon a 
“ small mass of parenchyma at their base. a Ostiolum. (E.A.8., del.) 
_. Fia.f. Five asci containing ascospores: muchenlarged. (E.A.S., del.) 
_ Fie.g. Aseospores. (E.A.S., del.) 
PLATE II. t Ae 
APPLE SCAB (FUSICLADIUM DENDRITICUM). 
_- Fie. 1. Shows the scab on the fruit. 
‘Fic. 2. A leaf attacked by the scab fungus. 
. Fig.3.’ A section through a portion of one of the spots on the fruit, showing the 
growth of the fungus; greatly magnified. 
Fic. 4. Spores of the fungus, greatly magnified ; four of them germinating. 
PEATE, GE 
BITTER-ROT OF APPLES (GLCZOSPORIUM FRUCTIGENUM ?).— LEAF-RUST OF CHERRY 
(PUCCINIA PRUNI-SPINOS 2).—BEET-RUST (UROMYCES BETA). 
Fig: 1. Section through piece of rotten apple showing an old pycnidium: a, thick . 
epidermis of fruit; b, fruit perenchyma: c, mycelium in tissues. The 
hyphe surrounding the pycnidium are composed of a series of short cells. 
. Section showing pycnidium and hyphe after the formation of spores has 
ceased ; a, mycelium in fruit tissues. 
A, tuft of spore-bearing hyphz; a, spore. 2B, spores much enlarged ;'a, 
surface view ; b, optical section. 
. Germinating spores twenty-four hours in water; showing dark bodies 
formed on the germ filaments. D . 
Germinating spores eight hours in water. 
. Uredospores of Puccinia pruni-spinose on peach. 
. Same on plum: a and b, in germination; ¢,¢, germ pores. ; 
. Paraphyses found abundantly in sori of Puccinia pruni-spinose. . 
; . 9. Teleutospores of same on plum: a a, surface view; 6b b, optical section. 
Fig. 10. Section through portion of sorus (uredo-stage) of Uromlyces betce: a a, 
cells of leaf tissue entirely surrounded by mycelium ; b, ruptured epider- 
mis; ¢, spores; dd, pedicels from which the spores have fallen. The 
mycelium masses together in spots beneath the epidermis forming astroma . 
on which the spores are borne. 
'Fia.11. Uredospores of same: a@, germ pore. 
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