38 HELENIUM TENUIFOLIUM. SLENDER-LEAVED SNEEZEWORT. 



cies commences to bloom as early as April, and continues until 

 November, which would make it as near an ever-blooming gar- 

 den plant as one could desire. Dr. Chapman, however, limits 

 the time to September. 



It may be noted that much of the effect of these yellow Com- 

 posites depends on their foliage, which very generally is rough 

 and coarse-looking. But in the case of our present species, the 

 long and slender leaves give a peculiar character of elegance to 

 the whole plant. 



Hdcniuni is not a large genus, and has only four representa- 

 tives in the eastern part of the United States, and a few more 

 in the western part. It was thought at one time to have some 

 resemblance to the Inula Helcnhmi, or Elecampane, and hence 

 its present name was given to it. Our knowledge of the Com- 

 posita; has, however, made such great strides since the time of 

 Linneeus that but few persons would now think of comparing our 

 o-enus with that of Imda. In structure it would best compare, 

 probably, with Gaillardia, a closely allied genus, although there 

 is really not much resemblance in the general appearance of the 

 two o-enera. But even in the structure there are important dif- 

 ferences, as in our plant the yellow, strap-shaped flowers, or the 

 ray-flowers, as the botanists would say, have perfect pistils, and 

 produce seeds, while in GaiUardici these ray-flowers are barren. 

 The greatest similarity will be found in the seeds or achenes, in 

 the form, which Is top-shaped in both genera, as well as in the 

 scales which constitute the pappus. Each floret of a Com- 

 posite is a complete little flower in itself (see Fig. 2), having its 

 reproductive organs in the centre (although these are sometimes 

 wanting), and two floral envelopes answering to the corolla and 

 the calyx of other flowers. The limb of the calyx, however, or 

 the pappus, as it is called in Composites, very commonly assumes 

 the shape of extremely slender bristles, which are popularly known 

 as down. These bristles adhere to the seed after it has ripened, 

 and an example known to everybody is found in the seeds of the 

 Dandelion. But in some Composites the pappus is more like an 



