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THE BOOK OF NATURE STUDY 



Groundsel. It is found in allotments, and practically in all fairly 

 rich cultivated ground. It may be distinguished from other 

 Chickweeds by the ovate leaves and by the hairy line which runs 

 along its stem, shifting from side to side at each node. 



The Sowthistle (Sonchus arvensis} is common in cornfields, and 

 may be recognised by the long, lanceolate leaves, curved down- 

 wards and bordered by small prickly teeth. The flower-heads 

 are large, of a bright yellow. A still more common weed of arable 



land is another species (Sonchus oleraceus), 

 which has rather smaller flower-heads with 

 pale yellow florets. 



The Speedwell most commonly found in 

 cultivated ground is Veronica agrestis, which 

 may be distinguished from other species 

 most closely resembling it by the narrow 

 sepals and the white lower petal of the 

 corolla. In allotments the Germander 

 Speedwell, the largest of the Veronicas, is 

 common. The structure of the flower 

 should be examined, for in many respects 

 it differs from the other genera of the 

 Scrophulariaceae. There are only four 

 petals and two stamens, which are placed 

 laterally. The complete number of stamens 

 in this order is five, as in Mullein ; many 

 genera, however, have only four, and in 

 some cases, as in the Figwort, a scale re- 

 presents the fifth stamen. The reduction of 

 stamens, from six to two, reaches its lowest limit in the Speedwells. 

 The lower petal is generally larger than the others, and forms a 

 landing-place for the flies which pollinate the flower. The stigma 

 stands straight up in the middle of the flower, and 

 is touched by the fly before the stamens, and by a 

 different part of its body. In trying to get the 

 honey, which is secreted by the gland below the 

 ovary, the insect comes in contact with the stamens, 

 from which it gets the pollen to carry to another 

 flower. The Scarlet Pimpernel (Anagallis arvensis) 



FIG. 36. Germander 

 Speedwell ( Veronica 

 Chamcedrys). 



FIG. 37. Fruit 

 of the Scarlet 

 Pimpernel. 



