VARIOUS FOOD-PLANTS 



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Fig. 59, I. — Jerusalem Artichoke. (Helianthus tuberosus, SunfloM'cr Family, 

 Composilw). Stem-tubens at base of stem, producing -slender roots. 

 (Vilmorin.) — The plant is a perennial herb, often 2 m. in height, closely 

 resembling an ordinary garden sunflower. 



MM 



Fig. 59, II. — Jerusalem Artichoke. Flower-cluster cut vertically to show 

 arrangement of the perfect florets forming a central mass or "disk," 

 the neutral ray-florets surrounding them, and the protecting bracts 

 or "involucre" looking like a calyx outside of all; the whole growing 

 from the so-called "receptacle" or expanded top, of the floral stalk. 

 (Baillon.) — Such a compact cluster of two kinds of flowers looks like one 

 huge fiower, and consequently becomes very attractive to many insects 

 which transfer its pollen advantageously. 



