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in a matter like this, it is unwise to assume on such negative evidence 

 that we are well off, for it is quite possible that these diseases are 

 doing more damage than appears, simply because they work in such an 

 obscure, hidden and ill-understood manner. I propose therefore to 

 recount the particulars of some of the instances that have come under 

 my notice in the hope that greater watchfulness may be exercised. 



On a later page, under the head of a " Disease of Larkspur," will be 

 found the particulars of a definite case of the kind we are considering. 

 Here the plants were killed outright, dying suddenly when full grown 

 from the effects of a sort of root rot or collar rot. Plants of other 

 sorts, such as Gladiolus, in the same gardens were also affected in a 

 like manner. 



Some years ago Mr. Scobie of Maitland called attention to a disease 

 occurring in his vineyard which presented some features that led me 

 to the conclusion not only that vines are subject to attacks of this kind, 

 which would be merely a confirmation of a former article on Pourridie, 

 but that it is to be feared especially in the vineyards in the moister 

 districts of the State. The case was not a very clearly defined one, 

 for there appeared to be several causes at work, and it was impossible 

 to unravel all the tangled threads of evidence. Several fungi that 

 would account for some damage were found on the leaves of the vines, 

 but in other instances the roots were found to be in an unhealthy 

 condition. 



The affected vines shed their leaves before ripening their fruit and 

 in consequence the fruit ripened in an abnormal manner. It appears 

 that this was not in all cases an evil, as Mr. Scobie related that one 

 year he netted more from the diseased vines than from the sound ones. 

 Instead of being black as they should have been, the berries were 

 amber coloured, and had a fair flavour. The disease appeared 

 to skip about from year to year, and to be of a not very, serious 

 nature. 



From this it will be seen that the evidence was not very clear. 



Suspecting the disease might be the beginnings of the so-called 

 Californian Disease, Mr. Scobie sent specimens to Prof. Pierce of 

 Santa Ana, for an authoritative decision and received the comforting 

 reply that the disease was not the one passing under that name in the 

 United States. 



A search on the leaves that had been shed by the vines in the 

 premature manner described showed that two fungi were present, the 

 Tufted Leaf Blight of the vine, already described in this Gazette as a 

 pest of the vine, and an AUernaria of precisely the form described in 

 connection with Take-all of wheat, a fungus that is not at all uncommon 

 on decaying vegetation. 



It was plain however that these would not account for all the 

 damage done, even if they did account for some of it, and moreover it 

 was difficult to see why healthy vines should exist alongside diseased 

 ones if these fungi were the prime cause of the disease in such cases. 

 When diseases are spread by means of spores borne on the wind it is 

 customary to see plants attacked in a rather uniform manner unless 

 there are marked variations in the adjacent plants, such as variation 

 in variety and hence in susceptibility. 



