1066 de Fr aine — The Structure and Affinities of Sutcliffia. 
EXPLANATION OF PLATES XCI AND XCII. 
Illustrating Miss de Frame’s paper on Sutcliffia. 
The photographs were taken by Mr. F. Pittock, of the Zoological Department, University 
College, London. 
PLATE XCI. 
Fig. i. Transverse section of the stele and some of the surrounding tissues, from Section V. 
M «= stele ; a = meristele still attached to M ; a 1 = meristele just detached from a; 7, / 3 l , and 
/ 3 2 = meristeles ; e = extrafascicular strands, x 2§ . 
Fig. 2. Longitudinal section from the primary wood of stele, to show xylem-parenchyma, par. 
p.xy. ~ primary tracheides. From Section 66. x 55. 
Fig. 3. Longitudinal section through part of the wood, from Section 76. p.xy. = spiral elements 
of protoxylem ; xy. 1 = primary xylem ; xy. 2 = secondary xylem. x 55. 
Fig. 4. Longitudinal section through part of the secondary tissues, showing the long, tapering 
elements of the secondary phloem, s.ph. xy 1 = secondary xylem ; m.r. ~ medullary ray. From 
Section 71. x 55. 
Fig. 5. Longitudinal section through cortical region, showing strand of isodiametric tracheides, 
i.t., and parts of ordinary secondary tracheides, o.t. From Section 59. x 220. 
PLATE XCII. 
Fig. 6. Transverse section of accessory vascular strand, cut somewhat obliquely, from Section 
40. s.ph. — secondary phloem ; xy.2 = secondary wood ; i.t. = isodiametric tracheides. x 55- 
Fig. 7. Part of central portion of Fig. 6, enlarged to show the isodiametric tracheides, i.t. 
x 220. 
