94 FLOWERS. 



(50) Chamomile Flowers. 



The double or nearly double flower-heads of cultivated plants 

 of Anthemisnobilis, Linn. (N.O. Composite). 



The florets of the ray and the majority of those of the disc 

 are white and furnished with ligulate corollas, which are lanceo- 

 late and terminate in a truncate three-toothed apex. In the 

 centre there are usually a few inconspicuous, yellow, tubular 

 florets to be found. The florets spring from the axils of lanceo- 

 late, obtuse palese inserted upon a conical receptacle. The 

 palese are scarious at the margin, and often fringed near the apex. 



The epidermal cells of the ligulate corollas vary in shape and 

 appearance according to their position on the ligula. Those on 

 the tubular part near the base are elongated and slightly 

 striated ; at this point the epidermis bears numerous pluri- 

 cellular glands possessing the structure common to the oil 

 glands of plants belonging to the order Compositse (go, g'o'). 

 Towards the apex the epidermis of the upper surface is destitute 

 of glands, but is provided with a number of papillae, and these 

 produce considerable variation in its aspect in different posi- 

 tions ; the lower epidermis is composed of sinuate, striated 

 cells, amongst which numerous stomata, glands, and simple 

 pluricellular hairs are to be found. 



The epidermal cells of the involucral bracts vary accord- 

 ing to their position on the bract. At the apex and on the 

 margins they are long and fusiform with but slightly thickened 

 walls ; near the median line and over the nbro-vascular bundles 

 they are elongated and provided with thickened pitted walls ; 

 near the base they are polygonal and isodiametric. Towards the 

 base the epidermis also bears numerous stomata, hairs and 

 glands. In the receptacle at the point where the bracts are 

 inserted there are sclerenchymatous cells. 



The style is composed of small cells rich in rosette-crystals of 

 calcium oxalate ; the stigmata are provided with characteristic 

 papillae. 



The diagnostic characters of chamomile flowers are : 



(a) The cells of the lower epidermis of the ligulate corolla ; 



they have wavy walls and striated cuticle. 



(b) The papillose upper epidermis of the same. 



(c) The characteristic oil glands. 



d) The elongated cells of the scarious margins of the 

 tracts. 



