Wernham, The Systematic Anatomy of the genus (Janephora. 



457 



At more or less frequent intervals, associatcd with the primary 

 xylem. are patches of parenchyraatoiis tissue (xy. p.J, consistin^'- 

 of sinall thin-walled cells of polygonal outline, 'i'liis may represent 

 xylem parenchyma, but in the absence of developmental details 

 no deflnite assertion can be made. There are no medullary rays, 

 but tlie wood is interrupted at frequent intervals by rays of fibres, 

 sometimes as much as three cells wide as seen in transverse 

 section. 



The phloem, which is too perished to be investigated with 

 much profit, takes the form of a narrow band surrounding the 



Fig. 3, c. 



Fig. 3. Diagrams of the petioles of (a) Ganephora madagascariensis, 



(b) C. angustifolia, (c) G. Ooudotii, in transverse section. 



xy. Xylem, lined; ph. phloem, dotted; sc. fibres, small circles; ground parenchyma left 



blank; l.b. lateral vascular Strands; for f. see text aud Fig. 4. 



xylem; the cell-walls are thin, and tannin is abundant. Calcium 

 Oxalate, in the form of crystal sand, occurs but is relatively rare 

 in the phloem. 



Immediately external to the phloem in transverse section 

 appears an unbroken sheath (sh.) , one to two cells broad, of rather 

 small sclerenchymatous fibres, with very thick walls and lumina 

 almost obliterated. 



The cortex consists of larg-e round cells, as seen in transverse 

 section, with relatively thin walls. Tannin is abundant, especially 



