XNXviii PROCEEDINGS OF THE ROYAL HORTICULTURAL SOCIETY. 



Scientific Committee, Apeil 19, 1904. 

 Dr. Masters, F.R.S., in the Chair, and ten members present. 



Pear-tree and Scale Insect. — Mr. Saunders, F.L.S., reported as follows 

 on a specimen received from Mr. Ward, Falmouth : — " The insect on the 

 spur of the Pear tree is one of the scale insects, ' the mussel scale ' (Myti- 

 laspis pomornm), a very common pest on Apple trees. They may be got 

 rid of by painting the infested parts with eight ounces of soft-soap dis- 

 solved in a gallon of water rubbed well into any inequalities of the bark. 

 Do not only paint just the parts where the insects are, but for some 

 distance up and down the stem or shoot, for these insects when young are 

 active, and crawl freely about the trees ; they are then so small and in- 

 conspicuous that they may readily be overlooked." 



Pear-scab. — Dr. Cooke, V.M.H., replied to inquiries on the two 

 following subjects : — " One of the many forms of Pear-scab, Fusicladium 

 pyrinum, is now attacking young Pear-shoots in some localities, forming 

 black patches, but at present without any production of the mould. This 

 is so well known on Pear and Apple, both on foliage and fruit, that it 

 needs no description. Freely spraying with a solution of sulphate of iron 

 should not be omitted at this season of the year." 



American Violet Disease. — " The American Violet disease, culminating 

 in Alternaria, which has been fully described in the Journal R.H.S. 

 vol. xxvii. p. 27, pi. ii., fig. 25, is again appearing in several localities, and 

 is a most dangerous and destructive parasite. At present we have found 

 no conidia on the spots, so that the destruction of the diseased plants will 

 assist in checking its dissemination." 



Biological Analogy. — Dr. Cooke read the following interesting note on 

 diseases : — " I venture to call the attention of the Committee to a remark- 

 able instance of what I have termed 'bL logical analogy.' The Board of 

 Agriculture, in a circular recently issued, states that a contagious disease 

 affecting horses, called epizcotic lymphangitis, has made its appearance in 

 this country. After describing its principal features it goes on to say that 

 ' an organism is the cause of the malady, and it is easily transferred from 

 the wound of a diseased horse to a wound on another horse not affected. 

 The most common means of such transfer is by the agency of sponges, 

 rubbers, brushes, &c.' This is precisely analrgous to what takes place 

 with the wound parasites of trees of fungoid origin, and it is interesting 

 to observe and watch such cases, since the treatment which succeeds in 

 one may be equally successful in the other. It may be added as sugges- 

 tive that in the case cf diphtheria in the human subject treatment with 

 sulphur has proved eminently successful ; in like manner is the same 

 remedy applied to the Vine O'idium and the Rose mildew, both of which 

 in habit bear a resemblance to diphtheria." 



Cabbage-leaf with Funnel- shaped Excrescences.— My. Holmes, F.L.S., 

 sent an example of this not uncommon phenomenon ; it is outgrowth 

 analogous to those on " crested " corollas, and is comparable with ovules 

 when metamorphosed into foliaceous appendages. 



Wood Sorrel icith deep Hose- coloured Flowers. — Mr. Holmes also sent 

 a plant of Oxalis Acetosella " growing among the ordinary form with 



