124 



PHYCOMYCETES. 



is very frequent on wild and cultivated Cruciferae throughout 

 the whole world, and causes deformation of shoot, leaf, and flower. 



FIG. 34. Cyatopus Candidas. 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. E, Swarm-spores in motile 

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

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

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

 unseen. (After De Bary.) 



Fin. 35. Flower of Radish (Raphanus sit.tirtui) hypsrtrophied by 

 Candida*. The much-enlarged ovary stands out in the centre. The anthers are 

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

 somewhat enlarged. (Specimen from Botanical Museum of Erlangen, and 

 photographed by Dr. Brims.) 



The conidiai cushions form thick white stripes with a porcellaneous 

 appearance, by which they are easily distinguished from the 

 cushions of Peronospora parasitica often present on the same plant. 



