Shriveling of Grapes. 87 



of cases, in order that we may seek, with any prospect of suc- 

 cess, for the cure or preventive of an evil, we must first endea- 

 vour to discover its cause. Every cultivator has a theory of his 

 own on the shriveling of grapes, but it would be extremely 

 difficult to find any two which agree. One attributes the dis- 

 ease to too much heat; another, to too little; a third, to damp ; 

 a fourth, to bad ventilation ; a fifth, to friction ; a sixth, to the 

 irregular expansion of the flowers, by which some of the berries 

 get the start of the others, and rob them of their due share of 

 nourishment and support; and a seventh, to some other cause. 



That some of these theories are wholly untenable, I think will 

 be evident from the following description of the disease. Shri- 

 veling does not manifest itself until the berries are colouring : 

 up to that period, the infected ones continue to increase, and 

 swell equally with the others ; they appear equally healthy, and, 

 in fact, it is impossible, I think, to distinguish them : but sud- 

 denly, whilst some, varying in number according to the extent 

 of the disease (and sometimes only a few berries), begin to be 

 infected, the remaining berries (forming sometimes nearly the 

 whole of the bunch) continue to deepen in colour, and gradually 

 become black ; while the others (the diseased ones) suddenly 

 cease to colour, but remain of a brownish red tinge ; and, al- 

 though they at first appear full and plump, and sometimes have 

 a considerable degree of bloom, they gradually shrivel and wither 

 up, as in the process of drying grapes into raisins, and, if tasted, 

 have a disagreeable sour flavour, scarcely any of the saccharine 

 principle being present. 



The disease must not be mistaken for " want of colour." In 

 this latter case, although the berries are not so black as they 

 should be, and, consequently, have not the proper degree of 

 flavour (for the blacker the grape, apparently the greater the 

 flavour), still they are not sour, and do not wither. Upon ex- 

 amining the diseased berries themselves, we do not discover any 

 thing to account for these effects ; but, upon looking at their 

 foot stalks, these appear black and withered in the centre, as 

 if they had been pinched with the finger and thumb ; some- 

 times, also, the main stalk presents a similar appearance. Here, 

 then, seems to be the seat of the disease ; but how long this may 

 have been in progress is uncertain : its course is, probably, 

 rapid, although obscure, and hitherto only observed at its last 

 stage, and then by its effects. 



Now, after a careful and attentive consideration of these ap- 

 pearances, I cannot think they should be attributed to friction, 

 or the irregular expansion of the flowers; but I am induced to 

 suspect that they may be referred to one of these two causes : 

 either the presence of a minute fungus, similar to the rust and 

 smut in corn, mildew, and other allied fungi; or to the at- 



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