124 



I'HYCOMYCKTES. 



is very frequent on wild and cultivated Cruciferae throughout 

 the wliole world, and causes deformation of shoot, leaf, and tiower. 



Fig. 31. — Ci/Ktopus caHdiihtn. B, Conidiophores isolated from the cushion ; the 

 conidia or sporangia are united by intermediate cells. C, Sporangia breaking up 

 to form swarm-spores. D, Swarm-spores escaping, is', Swarm-spores in motile 

 condition. /■', Swarm-spores come to rest and germinating. G, Two germ-tubes 

 entering a stoma of Lepidium sativum ; the stoma is shown from the inside, so 

 that the spores from which the germ-tubes arise are pn the outer surface and 

 unseen. (After iJe Bary.) 



Fio. 35.— Flower of Radish (Raphanus sativus) hypertrophied by Ci/stojms 

 caaduli's. The much-enlarged ovary stands out in the centre. The anthers are 

 leaf-like ; the petals are mucli enlarged and hang downwards ; the sepals are 

 somewhat enlarged. (Specimen from Botanical Musoinn of Krlangcn, and 

 ph(jtographed by Dr. Bnnis.) 



The conidial cushions form thick white stripes with a porcellaneous 

 appearance, by which they are easily distinguished from the 

 cushions of Piromspora parasitica often present on the same plant. 



