SlTDIfö IN THE EFFECT OF UÖNTaEN RAYS. ETC. 255 



GomvALD ScHWAUZ (1907) iuYCsti<j;jite(l tlic reLitiuu l)et\\eon tlio gi-<wle 

 of metabolism nud the seusibilitj'^ to R'iutj^u r.iys ujiou Avena scUiva ivnd 

 Vicia fahl. Tlie frrrttle of metiibolism iu dried seeds is iu miuiimim dep^ree, sj 

 tlie seeds a,ve iu the restiiip; sfcite ; l)ut if thej* su-e put iuta ■\vjiter, thej' sion 

 l»fj;iu to raotiilwhze aud the riuhcle aud phiuaile sprout h-oiii the eml)ry(5. 

 Such ch-ied seeds were exposed by him to rays of 200 II and so'mi. Tlio 

 '200 H-plaiits devoloi^ed as well as the mihradiated controls aud there was uo 

 differcuc-o Ix'twwu therei. 



But Avcna saliva of 2 days steeping, divided iutj two parts, one half 

 t.iken as coutrol aud the other half exposed to the rays of 6 H aud placed in 

 a dish (iu water), showed during the first 3 days no chÖerence between the 

 couh'ol aud G H-soeds, but on the fourth day the latter appeared iu a special 

 stiitt) and ou tl>e eighth cLty the 6B[-socdliugs were only one-third of tlie 

 length of the control. He ob33rved this reLition also in Vicia faha and 

 concluded tiiat " die Böntgenlichtempfindlichkoit der Zelleu ist ihi-er Stoff- 

 Mechselgrüße gerade proportion.!,!". Moreover, ho stated under the hea<;liug 

 ' Vergleich der Ilüntgenwirkimg mit der Lichtwirkimg auf die Pflanze ', iu a 

 Supplement tj liis pajxji', that " wachstumhemmend und chlorophyll bildend 

 wirken also die kurzwelligen ultr.u'ioletteu Sti'ahlen. Die Röntgenstrahlen 

 reiheu sich hier au. Phjniologisch hat che Ulti'aviolettwirkuug auf die Haut große 

 Ähnlichkeit mit der Koutgenwirkuug auf dieselte. — Au? den vorstehenden Ver- 

 suchen crgil)t sich uun ein weitei-er Parallelismus zwischen diesen Strahleuarten. 

 Auch pflanzenphj'siologisch verhielten sich die Röutgensti'ahleu im Wesen den 

 ultravioletten Lichtsti'ahlen analog"'. 



Schmidt (1910) steeped tlie seeds of sweet peas for Q hom's, exposed 

 them to the rays of -j H, -k- H, 1 .25 H, 2.5 H aud 5 H, aud put them into the 

 soil. Tlie former four groups developed better than the control and the 5 H 

 aud bore many fraits. Fm-ther, 5 seedlings (c:i. 2 cm.), which had l)een 

 geriniuated iu the soil, were used .and 1 H was given to the middle, 10 H to 

 the left and 20 H to the right liand side of the row, theu the seedhngs were 

 jigain phuited into the soil. At the end of this experiment, the 10 H- and 20 H- 

 pLmts reached onlj- 5 cm. in shoot-leugth, but the other three reached 10-15 cm. 



1. Jlitteihmgen ans dem Lnborntorium für radijlogische Dingaostik und Therapie, Bd. 1, 

 Heft 2, 1907. pp. 03-95. 



