CORN SOW-THISTLE 



139 



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is tall, simple, with radical leaves divided, with lobes enlarged upwards 

 the lobes turned back, heart-shaped at the base, the leaves being 

 alternate, clasping, smooth, pale below, dark-green above. The edges 

 are lined with prickles. Some leaves are linear-acute higher up. 



The flowers are yellow, borne on flower-stalks which are highly 

 glandular, with black or brown hairs, and in a sort of umbel also 

 like the leaf-like organs, which are unequal, keeled, very hairy, and 

 glandular. The fruit is 

 rough and transversely 

 downy, not beaked. The 

 pappus is stalkless, the 

 hairs numerous. 



The plant is i^ ft. 

 high. Flowers are to be 

 seen in July and August. 

 The plant is perennial. 



The flowers are as 

 conspicuous as those of 

 the Dandelion, and built 

 upon much the same 

 plan, attracting many 

 insects, though hidden, 

 or rather appearing just 

 above the corn before 

 it is ripe. The corolla is 

 yellow, like that of most 

 hermaphrodite florets in 

 Compositae. Each floret 

 is tubular, with a white 

 tube, which is narrow 

 and beset with hairs 



above, to preserve the honey at the base of the stigmas, and the limb 

 is yellow, as long as the tube, with edges rolled from the back inwards. 



The stamens unite to form a cylinder, the two threadlike stigmas 

 are bent inwards, and the style is hairy above, with slender lobes. 

 Thus cross -pollination is rendered possible by the sweeping of the 

 pollen out of the tube away from the stigma. The plant is visited 

 by the Honey Bee, Bombns, Panurgus, Halictus, Nomada, Megachile, 

 Osmia, Syrphidse, Eristalis, Cheilosia, Conopidse, Sicus, Lepidoptera, 

 Hesperia, Coleoptera, Curculionidae, Spermophagus cardui, Malacoder- 

 mata, Malachius. 



CORN SOW-THISTLE (Sonchus arvensis, L.) 



