Cause of Curl in Potatoesi 233* 



Base. — Regular, irregular, shallow, deeply indented, open, narrow. 



Apex. — Regular, irregular, shallow, deeply indented, open, narrow. 



Calyx. — Large, small, medium, retained long, partly retained, not retained. 



Seeds. — Long, short, thin, thick, lean, turgid. 



Cell. — Large, small, open, capacious, hollow, compressed. 



Stones. — Large, small, clings, free, smooth, rugose, long, round, large, 



small, &c. 

 Kernel. — Bitter, less bitter, sweet. 

 Sutures. — Deep, shallow, &c. &c. 

 Size. — Large, medium, circumference from the stalk to the calyx in octems, 



round the middle in octems. 



My gouty hand prevents me from rendering this glossary, 

 as complete as I could wish ; but I send it to you as a memo- 

 randum, to go into the wide world as an uninstructed bant- 

 ling (having only learned its alphabet), to receive and perfect 

 its education under more able masters than myself. 



Yours, &c. 

 December, 1827. W. R. Y. 



Art. XIX. Remarks on the Cause of Curl in Potatoes. 

 By a Denbighshire Gardener. 



Sir, 



Since my last letter, inserted in your Magazine (Vol. III. 

 p. 19.), I have paid much attention to discover the cause of 

 curl in potatoes. I am now convinced that it is occasioned 

 by the depredations of a small worm. In the presence of 

 several witnesses, • and at different times, I took up rows of 

 potatoes ; some were curled, others not : on the healthy plants 

 not a worm could be found, but upon everj' one of the diseased 

 plants I invariably found them. They lodge at the bottom of 

 the stem, which, for an inch or more, is changed from its natural, 

 to a pale unhealthy, colour ; the ascent of the sap is obstructed, 

 and the leaves, not having a due supply, are deformed and 

 diminutive. In examining the cut of the potato I discovered 

 a small hole, which probably was the place where the e^g had 

 been laid, and where the worm was bred ; and, I suppose, as 

 soon as the set became soft, the insect found its way to the 

 stalk, where its damage is so visible. 



If, then, this be the cause of the disease (and I beg to repeat 

 that I have no doubt of it myself), I have now to offer an opi- 

 nion as to how it happens that potatoes taken up before they 

 are ripe escape the attack, while those which are fully ripe are 

 liable. On this point my own mind is satisfied that it can 

 only arise from the difference in the quality of the sap, con- 



