328 
Hill . — On the Roots of Bignonici . 
EXPLANATION OF FIGURES IN PLATE XXII. 
Illustrating Mr. Hill’s paper on Bignonia. 
All the Figures refer to Bignonia Unguis. 
Abbreviations : camb., cambium ; c. c., companion-cells ; co., cortex ; cr. ph ., 
crushed phloem; m. r., medullary ray; ph„ phloem; pxy protoxylem ; p. w., 
wedge of sunken phloem ; scl., sclerenchyma ; xy., xylem. 
Fig. i. Transverse section of a root. 
Fig. 2. Transverse section of an older part of the same root as the last (somewhat 
diagrammatic). 
Fig. 3. Similar section from another root. 
Fig. 4. Transverse section of an older root showing an early stage in the 
development of the sunken phloem. 
Fig. 5. Diagram of a transverse section of a root showing the sunken phloem 
well developed. 
