BY M. B. WELCH. 485 



though ahiiost completely blocked by a dark insoluble residue. la this case the 

 palisade tissues only occur towards the upper surface. This section was cut 

 from dried material 

 Fig. 5. 



E. terminalis ¥. v. M. Transverse leaf section with one duct, lu some 

 material of this species examined there was no evidence of duets, which are 

 apparently not well developed in the species. The palisade tissue extends right 

 a-cross the leaf, and stomata occur on either surface. 

 Fig. 6. 



E. Abergiana F. v. M. Transverse leaf section with two duets. The pali- 

 sade tissues are developed towards the upper surface only, and stomata occur 

 on the lower side. 



Plate xliv. 

 Figs. 1 and 2. x -15; Fig. 3. x 55; Fig. 4. x 50; Fig. 5. x 13; Fig. (i. x 17. 

 Fig. 1. 



E. ferruginea Schau. Transverse leaf section with two ducts. The palisade 

 tissue consists of long narrow cells and extends right across the leaf; stomata 

 are found on either surface. 

 Fig. 2. 



E. Watsoiiiana. Transveree leaf section with two small ducts. The palisade 

 tissue extends right across the leaf, and stomata are developed on either surface. 

 The upper xylem band in this section shows a decided break at a point nearer 

 the petiole than is usual. 

 Fig. 3. 



E. peltata P>enth. Transverse leaf section with two ducts. The contents 

 are bright yellow in colour and soluble in 90 per cent, alcohol. The palisade 

 extends right across tlie leaf, and stomata are equally developed on eitlier side. 

 Fig. 4. " 



E. eximia Schau. Transverse leaf section witli three distinct central ducts, 

 though two are normal. The contents are usually clear, light yellow, soluble in 

 90-95 per cent, alcohol. In this species a red pigment is often found in the 

 hypodermal cells of the mid-rib. The palisade tissue extends practically right 

 across the leaf, and stomata are on either surface. 

 Fig. 5. 



E. corymbosa Sm. Transverse section of stem showing normal arrangement 

 of four ducts in the corners of the pith. 

 Fig. G. 



A. laiiceolata Cav. Transverse section of young stem showing tlu-ec oil 

 ducts oriented towards the angles of the pith. 



Plate xlv. 

 Fiff. 1. X 50 ; Figs. 2, 3 and 6. x 30 ; Fig. 4. x 70 ; Fig. 5. x 40. 

 Fig. 1. 



E. dichromophloia F. v. M. Transverse leaf section with two small central 

 ducts. In the material examined of this species only one leaf duct was often 

 found with very little contents which were soluble in 90 per cent, alcohol. The 

 palisade tissue is directed towards the upper surface only. In the stems two 

 ducts were usually found, almost filled with thin-walled cellular tissue. 

 Fig. 2. 



E. haematoxiilon J. H. M. Transverse leaf section with three central ducts, 

 though two were normal in the material examined. Contents very pale yellow in 

 colour and soluble in 90 per cent, alcohol. The palisade tissue is developed 

 towards the upper surface, and stomata occur only on the lower epidermis. 



