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Rennert : Teratology of Arisaema 



initial sterile portion is expanded into a laminar structure of irreg- 

 ular outline^, and showing a few plaited foldings. 



No records have been found of monstrosities in Arisaema 

 Dracontium. One specimen of A. Dracontiitm in Dr. MacDougal's 

 collection shows a curious malformation of the tip of the spadix. 

 The spathe and spadix of this plant seem to be normal in every, 

 respect except that the tip of the spadix has grown out into a 

 crescent-shaped process, on one horn of which a minute elevation 

 may be seen (Fig. 2, JSF). 



Other malformations in both species of Arisaema are produced 

 by the action of the Aecidijim with which they are often infected. 

 The infected individuals develop earlier than the normal ones and 

 show leaves with diminished surfaces, crinkled laminae, and in- 



The spadices are variously distorted, and the 

 spathes have the terminal portion, constituting the hood, in an erect 

 position instead of drooping over the spadix. It is not known 

 whether the specimens developing earliest are most subject to in- 

 fection, or whether the presence of the fungus in the plant induces 

 earlier activity, although the latter seems more probable. 



The leaves of seedlings and offsets exhibit reversions to un- 

 usual forms in a very interesting manner, and will be discussed in 

 a future article. 



rolled margins. 



