2 THE JOURNAL OF INDIAN BOTANY. 



cells found in mesophyll. Clothing hairs in the form of flagellum trie- 

 homes. Glandular hairs biseriate and club-shaped. Collenchyma 

 composite and sub-epidermal in the axis. Wood composite. Medul- 

 lary rays 1-3 seriate. Medullary xylem bundles present. Pith formed 

 of cells with thickened and lignified walls. Some of the pith cells 

 holding dark granular contents and also rounded bodies. 



Eclipta erecta L. Figs. — 178, 179. Very herbaceous. Stomata 

 depressed. Mesophyll composed of arm-palisade cells. Clothing hairs 

 absent. Glandular hairs depressed, biseriate and spherical. Collen- 

 chyma sub-epidermal in the axis. Wood composite and deeply lobed 

 on the inner side. Pith formed of thin-walled cells. 



Echinops echinatus B.— Figs. 180, 181 , 182. Very herbaceous. 

 Stomata elevated. Mesophyll formed of palisade tissue on the adaxial 

 side and of arm-palisade tissue on the abaxial side. Clothing hairs in 

 the form of flagellum trie homes. Glandular hairs long-stalked and 

 with an irregularly divided spherical head. Collenchyma sub-epi- 

 dermal in the axis. Endodermis formed of large thin-walled cells. 

 Wood composed of large xylem bundles alternating with small ones. 

 Pith consisting of thin-walled cells. 



Volutarella divaricata Bth.— Fig. 183. Very herbaceous. 

 Stomata elevated. Mesophyll isobilateral. Clothing hairs absent. 

 Glandular hairs long-stalked and with a head irregularly divided. 

 Collenchyma sub-epidermal in the axis. Wood more or less composite. 

 Pith formed of thin-walled cells. 



Dicoma tomentosa Cass.— Figs. 184, 185, 186, 187, 188, 189. 

 Herbaceous. Stomata depressed. Mesophyll composed of palisade 

 tissue on the upper side and of arm-palisade tissue on the lower. 

 Clothing hairs in the form of uniseriate flagellum trichomes. Glan- 

 dular hairs depressed, uniseriate and spherical. Collenchyma strength- 

 ening the ribs of the axis. Wood not composite. Pith consisting of 

 thin-walled cells. 



Launaea chondrilloides II. f — Figs. 190. Herbaceous. Stomata 

 depressed on the leaf but elevated on the axis. Mesophyll formed of 

 arm-palisade cells. Clothing and glandular hairs absent. Collenchyma 

 not developed in cortex. Wood not composite. Assimilatory tissue 

 in the axis formed of palisade tissue. Pith formed of thin-walled 



cells. 



Structure of the Leaf: — The epidermal cells are alike on both the 

 sides and have the outer walls greatly thickened and convexly arched 

 outwards. The lateral walls are thin and undulated; inner walls 

 are usually thickened. The cells at the margin are rounded and have 

 outer walls toothed in D. tomentosa and papillose in other members. 



