\OVEMBER 9, 1912. 



THE GARDENERS' MAGAZINE 



853 



CONFERENCE 



ON 



4- 



ORCHIDS. 



It is many years ago, in 1885 to be cor- 

 rect, since the Royal Horticultural Society 

 held a conference in connection with Orchids^ 

 their cultivation and hybridisation. This 

 conference was held at the society's old gar- 

 dens at Chiswick. 



On the present occasion Mr. J. Gurney 

 Fowler, the society's treasoirer, presided, and 

 at the opening of the Conference, at 10 a.m. 

 on Wednesday, November 6, referred to the 

 splendid autumn exhibition of orchids in the 

 Royal Horticultural Hall, belowj and pointed 

 out that when the exhibition was suggested 

 the idea of holding* a conference in conjunc- 

 tion with it was well received, and now car- 

 ried into effect. 



There was a fair attendance, including : 

 Sir G. Holford, Sir Harry J. Yeitch, Messrs. 



remained in close contact for a while and 

 then fused intimately. From this fused 

 mass, forming a single cell or zygote, arose 

 the material that eventually produced the 

 desired plant. Professor Keeble pointed out 

 that it was formerly believed that the egg 

 cell of the ovule could not deveh)p without 

 the influence of the male element (pollen). 

 But it was now found that unfertile eggs of 

 sea urchins could be made to produce young 

 by means of chemical stimulus and without 



the intervention of the male element (sper- 

 matozoa). Many plants do 



without pollination, as in the 

 weeds, alchemillas, and other part hcnogcne. 

 tic plants, and here, it would seem, that de- 

 velopment was due to mechanical stimulus. 

 Frogs had been produced from unfertile eggs 



produce seeds 

 case of hawk- 



De Barri Crawshay pointed out that he had 

 proved this problem in one c^se, as he 

 croHsed Odontoglossum Harryanum with O. 

 Laml>eanum, and the fine, slightly spotted 

 O. crispum Ange]^ and the ret^uMs were O. 

 crispum-llarryanum and O. Row^fieldiense, 

 these reprceienting distinct hybrids. 



APPLICATION OF GENETICS TO 



ORCHID BRKKDINCJ. 



Major Hurst. F.L.S., one of our leading 

 workers in Mendelism, re:id a highly tech- 

 nical ])aiK^r u|x>n the alcove Hubj<K!t. He 

 paid tribute to the great work of the R.H.S. 

 to propagate the science of genetics at seve- 

 ral conferenci^, and then pointed out that 

 among' orchids 4<) genera and 300 specie* 

 had been already used in breeding, and there 



G.M.S20 



CAITLEYA rEKTKKSI WI-STONBIRT VABII7n^ 



A magnificent cattleya, the deep purple colouring 

 and petals. F.C.C., R.H.S., November 5. Sir 



and gold-marked thrf)at of the labellum l>eing admirably ^et off hy the wliite r-epals 

 George Holford (grower, Mr. H. Alexander), Wcstonliirt. Tct^uuv. ( Jluuct-ter. 



(See p. 86.3.) 



R. A. Rolfe, De Barri Crawshay, J. Fraser, 

 ^V. Cobb, F. Hanbury, J. O Brien, W. H. 

 ^^hite, H. Alexander Gurney Wilson, F. J. 

 Hiittenden. H. G. Thwaites, Briscoe, Curtis, 

 Hatcher, J. Cypher, etc. 



PHYSIOLOGY OF FERTILISATION OF 



ORCHIDS. 



Professor F. Keeble, M. A., D.Sc., dealt with 

 this intricate and vastly interesting subject. 

 He pointed out that a long series of events 

 occurred beween the application of the pollen 

 to the stigma, and the harvesting of the 

 seeds. He covered fairly well-understood 

 pound when, by means of slides, he showed 

 now the pollen germinates on the stigmatic 

 surface and sends its pollen tubes down the 

 column, carrying its nucleus down to the 

 ^^'^y, entering the ovule (or unfertile aiul 

 ^mbryo seed), and discharging that iiuclvus 

 male element) into close contact with the 

 i^male nucleus. He showed how the nticlei 



stimulated by puncturing, and in the case of 

 Zvgoi>etalum" Mackayi, fertdlieed with pollen 

 of odontoglossum, the resulting seedlings 

 showed no hybrid influence at all, but came 

 true Zygopetalum Mackayi, thus also sug- 

 gesting stimulative influence only. Professor 

 keeble pointed out that the effects of pol- 

 lination might be threefold— (1) fertilisation ; 

 (2) stimulative; and (3) chemical. 



Mr. O'Brien referred to several instances 

 of the stimulative influence of grit or dust 

 ui>on the stigma of flowers. An interesting 

 matter arose in the discusvsion, and it Mas 

 wliether there was any possibility of two 

 pollen tubes fcrt ilisiii^r '>iie ovule. I*rof<'- :)r 

 Keeble said not. 'Vhvn aro>c tlic fpuistitm ot 

 whether a Howrr could successfully fer- 

 tilised wi(]i -i'vcral kinds of pollen (i.e., 

 pollen from different spivies or genera), with 

 the result that distinct hybrids could be pro- 

 duced from the same pod of seeds. Profes- 

 s'<ir Keeble cousidored it possible, and Mr. 



were no fewer than 2,000 primary hybrids, 

 while secondarv hvbrids and varietal forme 

 were beyond computation. Major Hurst 

 pointed out how few fine hybrids were ob- 

 tained from the large batches of seedlings 

 raised, and it would l>e a great advance if 

 things could be so managed that there were 

 fewer weeds '* in proportion to the '* de- 

 sirables.*' The only way, said Major Hurst, 

 wiis along the lines of Mendclian principles, 

 and already good work was being done in this 

 direction. Major Hurst considered that it 

 w.i> inH't'>>;ny to secure pure breeding or- 



c]iid-> tnr t^tud ])ur|K>ses, and so lal>el them 

 tlial tlicv could alwavs be identified, and 

 tlic divisionally ])rnpagated plants of a 

 kni)\vii ^-ood breeder w<Mild ncquii*e a value 

 and rvf)ut-;^tion such as that ]K>>sessed by 

 a tine sire or brood mare among horses. 



A good-looking orchid that gained a F.C.C. 

 need not necessarily prove a good stud jdant, 

 but the parents of such n luj^h-class orchid 



