MONSTROSITIES AND MALFORMATIONS. 247 



others they show no evidence of doing so. The 

 whole practice of horticulture and agriculture 

 abounds in examples of teratological sports or 

 varieties which are transmissible by seeds, bud- 

 ding and grafting, and other means ^.^^. double 

 flowers, hypertrophied floral organs (cauliflowers), 

 seedless grapes and ' oranges, crested ferns, etc. ; 

 and even when such varieties could not live as 

 such in a state of nature, there is evidence to 

 show that many of them readily revert to the 

 original seed-bearing or single condition, and 

 adapt themselves to the altered environment. 



Every part of the plant may exhibit teratological 

 changes, and I shall for the most part select cases 

 in illustration which indicate approach to patho- 

 logical states, and group with them cases known 

 to be pathological in origin. 



Atrophy is a common phenomenon denoting 

 dwindling or reductions in size of organs due 

 to insufficient nutrition, or arrest of growth from 

 various causes. 



Atrophy of leaves is a common result of the 

 attacks of parasitic fungi, even when the latter 

 induce local hypertrophy i.e. excessive growth of 

 particular parts, e.g. Synchytrium on Dandelions 

 and Anemones. Puccinia suaveolens causes partial 

 atrophy of the leaves of Thistles, Aecidium 

 Euphorbiae of those of Euphorbia. 



The carpels of Anemone are atrophied in plants 

 attacked by Aecidiian, and the whole flower is 

 suppressed in Cherries infested with Exoascus 

 Cerasi, while other fungi e.g. Cystopus, Exoasci, 



