464 DISEASES OF CULTIVATED PLANTS 



patch of greater or lesser extent becomes very soft ; soon 

 afterwards the greenish coating of mould appears at the sur- 

 face, and eventually the entire fruit is reduced to a semi-liquid 

 mass. When a case of oranges is opened on arrival in 

 England, absolutely rotten examples are found in close juxta- 

 position to perfectly sound fruit, proving that unless the skin 

 is bruised infection does not take place, although the sound 

 fruit is completely surrounded by a decaying mass teeming 

 with conidia and mycelium, owing to the wrapping paper 

 having been destroyed. 



The fungus is almost indistinguishable from Penicillium 

 glaucum in general appearance, just a little greener in tint ; it 

 is, however, at once distinguished by the elliptic-oblong 

 conidia, which vary in size, averaging 7-9 X4/. 



The remedy consists in exercising greater care in gathering 

 the fruit, so as to avoid bruising, and not to pack injured 

 fruit. All decaying fruit should be removed from the planta- 

 tions, and from the neighbourhood where the fruit is packed. 

 Penicillium glaucum (Link.) often becomes an injurious 

 parasite on nearly ripe fruit, and on foliage, etc., that has been 

 in any way injured, or from which a sugary sap escapes. 



This mainly arises from the presence of the fungus on de- 

 caying vegetable matter in the vicinity, fallen fruit, etc. Care 

 should be exercised in removing all such sources of infection, 

 as in nearly all instances spraying is impracticable when fruit 

 is nearly ripe. 



Mycelium effused, creeping, white, sterile hyphae creeping, 

 septate, interwoven ; conidiophores erect, apex penicillately 

 branched, branches single or in pairs, erect, once or twice 

 forked at the apex. Conidia produced in chains, globose or 

 broadly elliptical, smooth, hyaline, with a tinge of green, 4 \i 

 diam. The chains of conidia spring from the tips of the 

 ultimate branchlets. 



GLIOCLADIUM (Corda) 



Conidiophores erect, septate, penicillate above, branches 

 and branchlets septate, crowned by a common mucilaginous 

 head. Conidia acrogenous, irregularly massed together, 

 simple, surrounded by a gelatinous coat. 



Differs from Penicillium in the conidia not being produced 

 in chains, and in being involved in a mass of mucous forming 

 a glairy head. 



