531 



those which occur iu some sorts of apples. Several of them were 

 pushing forth strong buds when examined. 



The probability of the crop of the present season being infected by 

 planting partially diseased seed has now become the most important 

 inquiry ; and with a view of obtaining some information on this point, 

 a quantity of apple potatoes were selected, and divided into three 

 classes — those that were apparently sound, a second portion slightly 

 diseased, and a third more so. Of the first class, four tubers were 

 planted, one of them divided into two halves, which have produced 

 apparently healthy plants. An equal number of the second class 

 produced three plants, two of which became sickly, when about eight 

 inches over the surface, and were evidently decaying. On examining 

 the lower portion of the stems, they were found to be getting into a 

 putrid state, close to the old tubers, but no fungi had appeared on the 

 backs of the leaves ; the third plant remains apparently healthy, but 

 weak. None of the third class produced plants ; but, on examining 

 the mould, a few small, misshapen young tubers were found to have 

 been produced by one of the sets. 1 ought to state that the whole 

 were steeped an hour in lime and water before being planted. Dupli- 

 cates were planted without being steeped, which gave nearly similar 

 results. I have, however, observed, within the last week, that the 

 leaves of one of the plants raised from a diseased tuber, has become 

 infected with the fungus, Botrytis infestans, the same species which 

 was so general on the leaves of diseased potatoes last season. 



Cup potatoes were classed in the same manner, and two tubers of 

 each planted. The sound tubers have produced sound plants ; those 

 partially diseased produced plants very weak, and out of the two that 

 were most diseased, one produced a plant, the lower leaver of which 

 have been affected with the fungus, and it is otherwise very weakly. 



Two tubers, partially diseased, of the pink-eye variety, were plant- 

 ed, after dividing one of them separating the rose from the root 

 end, which produced two plants, one from the whole tuber, and one 

 from the rose end of the cut tuber : they are both strong and coming 

 into bloom. A few of the tips of the lower leaves of one of the plants 

 have shrivelled, on which the Botrytis has been observed. 



The last experiment was made on three diseased tubers — one of 

 each of the varieties of the potato I have already noticed. They were 

 cut in halves and allowed to dry on the flue, until the cuts were heal- 

 ed over before being planted, but none of them have produced plants. 



To ascertain whether the fungus, w^hich has prevailed so generally 

 on rotting potatoes, infected sound tubers when a few only were put 



