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visited by small insects, the fungus gnats. The insects find 

 their way in between spadix and spathe, the projection on 

 the spadix prevents the insect from getting out above. In- 

 sects can find their way out where the edges of the spathe 

 overlap, and Weed thinks that in older flowers the walls open 

 wider, at any rate, in many cases gnats perish in the prison 

 chamber. 



'— The Skunk Cabbage {Symplocarpus foetidus) has not 

 only a disagreeable odor, but also color. It grows in 

 swampy places and is visited by numerous flies that breed 

 in these marshy places. 



Oolocasia odora- Some of the aroids are pollinated 

 by snails. Delpino states that this species is pollinated 

 in this way. Mueller says: "The spadix is covered 

 in its whole length with normal and abortive stamens 

 and pistils; only female flowers occur in the lower, wider 

 part of the spathe, and they only are mature in the 

 first period. From this chamber an attractive odor 

 issues, and the snails are admitted by a narrow en- 

 trance. In the second stage this entrance closes, and the 

 anthers dehisce. Snails which creep onto the flower in this 

 stage seek vainly for the entrance, and dust themselves with 

 pollen, which they afterwards carry to the stigmas of 

 younger plants. Delpmo supposes that the" snails after 

 affecting cross fertilizatioUj are poisoned by an irritant 

 secretion within the chamber of tde spathe, and are so pre- 

 vented from devouring the flowers." 



