354 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1913. 



probability the same as that upon the roots of the parent plant. 

 This happy observation shed a ray of light; it explained all the 

 failures in cultivation experienced by growers^ as well as the reason 

 for their success when they placed the seeds about the base of the 

 mother plant. 



However, a new method of cultivation which was gaining ground 

 in the horticultural world seemed not to substantiate the preceding 

 explanation. Instead of placing the seeds at the base of the mother 

 plant some gardeners sowed them in earthenware saucers contain- 

 ing various substrata, such as sawdust. As they frequently obtained 

 successful results they maintained that it could not be a question 

 of infection by fungi from the roots, and the explanation given by 

 Mons. Noel Bernard which so revolutionized the ideas of horticul- 

 turists seemed to them still less admissible, in view of the fact that 

 their trials were always fruitless whenever a kind of white growth, 

 some mold or fungus, invaded the sawdust amid the fine orchid 

 seeds sown there. This unscientific objection was in vain, for on 

 making sections of the embryos developed upon the sawdust it was 

 found that they were always regularly infected by the fungus, which 

 invariably entered in the same manner, by the micropyle (sus- 

 pensor), and invaded the cells, producing there tightly rolled balls 

 of threads. This irrefutable observation did not completely solve the 

 question, for whence came the fungus in this case? This is still an 

 unsettled point. The first hypothesis which occurs to one is that 

 the fimgus is so abundant in the greenhouse that it infects the saw- 

 dust naturally, like the mold in a cheese cellar, whose presence en- 

 ables the manufacturer to obtain excellent products but whose ab-' 

 sence brings him ruin. Perhaps there is a simpler explanation — 

 that the gardener, naturally of a clever and often furtive disposition,' 

 has placed in the substratum fragments of roots which have thus 

 infected the seeds with their fungi. The last explanation seems to 

 me not at all improbable, because at the conclusion of Bernard's 

 investigation Mons. Denis, an orchid gi-ower of Midi, France, actu- 

 ally employed this method and obtained good results. When horti- 

 culturists thus employ subterfuges to deceive and throw off the track 

 disinterested investigators who are trying to perfect their industry 

 they make a mistake, for it is to their best interest to seek the intelli- 

 gent aid of science, which can guide their work and be of the great- 

 est assitance to them. It too often happens that they conceal mys- 

 teriously some trick of the trade, the reason for which they do not 

 understand, although it brings them success and may even be the 

 foundation of their fortune. It is easily imagined that they pro- 

 tect their secret with jealous care, but unhappily secrets can not be 

 kept indefinitely. 



