CHAPTER XXXIX. 



MONOCOTYLEDONS (Continued). 



Topic II : Monocotyledons with flowers on a Spadix 

 (Spadiciflorae). 



395. Lesson II. The arum family (araceae). — This family is 

 well represented by several plants. The skunk's cabbage 

 (Spathyema foetida), the " jack-in-the-pulpit, " also called 

 " Indian-turnip " (Arisaema triphyllum), shown in fig. 210, the 

 water arum (Calla palustris), and the sweet flag (Acorus cala- 

 mus) are members of this family, as also are the callas and 

 caladiums grown in conservatories. The parts of several of the 

 species of this family, especially the corm of the Indian turnip, 

 are very acrid to the taste. The floral parts are more or less 

 reduced. 



396. Relatives of the arum family. — Related to the arum 

 family are the ' ' duckweeds. ' ' Among the members of this 

 family are the most diminutive of the flowering plants, as well 

 as the most reduced floral structures. 



Other related families are the cat-tails and palms. In the 

 latter the spathe and spadix are of enormous size. The cocoa- 

 nut is the fruit of the cocoanut palm. 



Exercise 66. 



Indian -turnip. 



397. Staminate plants (sometimes called male plants). — Sketch an entire 

 plant showing the corm (the thickened perennial stem), the annual shoot with 

 leaves and spathe. Cut away one side of the spathe to expose the long com- 

 pact cluster of staminate (spadix) flowers within. Sketch the spadix, showing 

 the mass of stamens as well as the sterile part of the shoot above. Dissect off 

 from the axis feveral of the stamens. Note that the filament is very short, 

 and that the anther is irregularly lobed. 



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