Ixxvi PROCEEDINGS OF THE EOYAL HORTICULTURAL SOCIETY. 



Scientific Committee, June 12, 1906. 

 Dr. M. T. Masters, F.R.S., in the Chair, and eleven members present. 



Iris diseased. — The Irises shown at the last meeting from the Rev. 

 R. Meyer have rotten stems, the rhizomes as well as the basal part of the 

 leafy shoots being affected, and the plants finally died ; they were reported 

 upon by Mr. Massee, Y.M.H., as follows : — " The Iris has the bacterial 

 disease badly. No name seems to have been given to the germ, but the 

 disease was worked out by Dr. Hewlett. Nothing can be done now to 

 the plants but to remove the diseased rhizomes and fiU the holes with 

 quicklime. Next spring, before the plants move, two inches of the 

 surface soil should be removed and replaced by an equal mixture of fresh 

 soil and quicklime." The disease seems to be very prevalent this season, 

 and another specimen was received on this occasion from Chingford. 



Gardenias dying. — Mr. Massee also reported that " there was no 

 specific disease present in the Gardenia, but that it was a case of 

 imperfect cultivation. Gardenias are always difficult to manage, and 

 neglect in watering is strongly resented." 



Diseased Deodars. — Mr. Massee said that the deodars from Devon 

 were under examination, and that he would report upon them in due 

 course. 



Insects eating Iris. — Mr. Saunders, F.L.S., said that " the caterpillar 

 attacking Iris Delavayi, from York, is that of the iris wainscot moth, 

 Nonagria Sparganii, which feeds upon the common yellow Iris and on 

 other species. Handpicking is the only means of dealing with the pest. 

 The moth is a reddish-yellow one, measuring about an inch and a half 

 across the open wings." 



Potatoes failing. — Potatoes which had failed to grow, and others 

 which had produced very weak, spindly shoots, were received from two 

 localities — Romford (Essex) and Affpuddle (Dorset). Concerning the 

 former the sender says : — " The potatoes sent are of the variety called 

 ' Empress Queen.' They are from new Scotch seed grown in Fifeshire, 

 and planted in well-cultivated soil. They have been planted two months, 

 and only about half of them are through the ground, most of those that 

 are up being very weak. Those that are not up have in some cases not 

 started to grow, and look as if they never would do so, while others are 

 growing very weakly, and the sprouts seem to have some disease in 

 them. They appear to grow a certain length and then the stems go 

 rotten, and in some cases a weak sprout shoots out again. There are 

 nine acres so affected." Concerning those from Dorchester the grower 

 writes : — " Several lines of potatoes have been irregularly affected in the 

 manner of the tuber enclosed (having a very large number of weakly 

 shoots), and others in the neighbourhood are suffering in a similar way. 

 The seed appears sound and good, but, while part of the row comes 

 through all right, there are gaps where the first sprouts die away, and 

 only the second (sometimes none) come through. A patch of ' May 

 Queen ' is quite unaffected, and all were treated exactly alike. The seed 

 is fresh from Lincolnshire this year." It was remarked that investigations 

 in France had shown that this failure to grow was due to the fact that 



