EFFECT OF PARASITIC FUNGI ON THE FORM <>F HMsT-l'I.ANT. L'7 



The two first cases have already been considered. The arrest 

 of the flowers of anemone, as a result of Acci<fin/n ju/m-fnhnii, 

 is a further example of Case 2, and at the same time exemplifies 

 Case 4, in that the floral leaves become green foliage leave- 

 though of a very stunted kind. The petals of Cruciferae hypei- 

 trophied under the influence of Ci/*fji* niii<H<lnx often become 

 green, and at the same time much altered in shape. 



A particularly interesting case is presented by the develop- 

 ment of the stamens of the pistillate flowers of Lyi-lini* i/i,,;,-,, 

 infested by the mycelium of Uxfilayo riol.<'. These stamen- 

 normally remain rudimentary, but in the diseased abnormal 

 flowers become fully developed like those of the staminate 

 flowers, except that the spores of the parasite replace the 

 pollen in the anthers. Giard 1 has designated this phenomenon 

 as "castration parasitaire," and he distinguishes three modifica- 

 tions amongst unisexual flowers. 



(") Stamens appear in pistillate flowers ("androgene castration 

 parasitaire"). This occurs, as already mentioned, in pistillate 

 flowers of Z//'7/ ///.-, il'toim frequented by I'+tilmj,,. 



(1>) Ovarie.- are developed in staminate flowers ("castration 

 thelygen "). Kxamples : Carex praecox with r.s//A>v carids, 



Jtlirliln, ilnrti/lu'i,!,* with Til/' I"' I Hr/t linn nil . aild J //'//>y ""/,,/, 



prori IK-HI! I* with I'xtihii/ii andropogonis, 



(c) In flowers of either sex the sexual organs of the othei 

 appear in consequence of the influence of the parasite ("amphigeiie 

 castration parasitaire"). (iiard compares these cases with that 

 of the development of the organs of the latent sex in animal-. 

 ','/. of cock's leathers on an old hen, or growth of limn- on 

 castrated or " gimmer " animals. In both eases the phenomenon 

 is due to the same cause: in the animals the organs of the 

 latent sex appear as the result of the normal organs becoming 

 funetionless or bein- de.-tn.yeil by castration; in the plant- 

 through stimulation of the latent rudiments by the fnn-u- 

 which does not, however, cause suppression of the organs 

 already present. "In some respects the phenomenon is comparable 

 with what happen- when the terminal .-hoot of a tree is lost 

 and -..me nei-hboiirin'j lateral shoot turns vertically upward 

 to replaee it. 



The effect of i'miiii on the reprodiiet i\e organs of phu 

 1 Mangin and Giard, /.'////<( icient. >/ / l''i-nn<; ,i ,l, in /;./;///., |s-i 



