154 FRUITS, 



(78) Fennel Fruit. 



The fruit of Fceniculum capillaceum, Gilib. (N.O. Umbelli- 

 fera). 



The transverse section exhibits the following characters ; 



(1) An outer epidermis, composed of polygonal cells with 

 straight walls and furnished with stomata. 



(2) Parenchymatous tissue (mesocarp), composed of irregular 

 polygonal cells; many of these are characterised by their 

 reticulate or spiral thickening ; they are either isolated or form 

 groups in the ridges of the fruit, near the fibro-vascular 

 bundles. There are six large vittse, easily distinguished by the 

 brown colour of their walls ; four are situated on the dorsal 

 surface of the fruit, and two on the commissural. The bundles 

 are composed of tracheids with a few bast cells, supported by 

 a mass of sclerenchymatous fibres with pitted walls. 



(3) An inner epidermis, composed of a single layer of narrow, 

 elongated cells ; these cells are arranged in groups of some six 

 or more, with their long axes parallel to one another, but at 

 right angles or obliquely to the long axes of the cells of other 

 groups. 



(4) A seed coat] this consists of a single layer of brown 

 polygonal cells. 



(5) An endosperm made up of rather thick walled polygonal 

 cells, containing aleurone grains, fixed oil, and protoplasm. 

 Some of the aleurone grains contain a rounded globoid, others 

 a small rosette of calcium oxalate. 



The diagnostic characters of powdered fennel are: 



(a) The spiral and reticulate cells of the mesocarp. 



(b) The narrow cells of the inner epidermis and their 

 characteristic arrangement. 



(c) The absence of hairs. 



(d) The thick-walled endosperm cells. 



