72 Mas fen . — The Relation of Root to Stem in Catamites. 
the leaf-trace bundles, i. e. at the node, and not above them as in stem- 
branches ; the roots pursue a somewhat downwardly directed course in 
passing through the wood of the main axis (the actual angle of divergence 
seems to vary greatly in different cases) ; the internodal (carinal) canals, 
representing the disorganized protoxylems, which are characteristic of the 
stem-branches even when embedded in the wood of the main axis, are not 
present in the roots ; the narrowing of the pith of the root before it joins 
with that of the stem appears to be more gradual than in the stem-branches, 
otherwise they appear to be very similar to one another, and there is 
usually a differentiation of the pith into distinct inner and outer regions. 
The pith of the large roots usually became hollow by the destruction of the 
thinner-walled central portion. In nearly all cases there is a wide band 
of persistent pith, i. e. the whole of the pith does not usually disappear as in 
the larger stems. 
In conclusion, I wish to express my obligation to Dr. D. H. Scott, 
M.A., F.R.S., who suggested the investigation and supplied the slides on 
which the work is based. He has also allowed the work to be done in 
the Jodrell Laboratory at Kew, and has kindly afforded much help during 
its progress. My thanks are also due to Mr. L. A. Boodle, F.L.S., for great 
assistance in connexion with the photographs which accompany this paper, 
and to Mr. W. W. Midgley, F.R.Met.S., who kindly supplied the photograph 
from which Fig. i (PI. I) is made. 
EXPLANATION OF FIGURES IN PLATES I and II. 
Illustrating Mr. Maslen’s paper on ‘ The Relation of Root to Stem in Catamites.' 
PLATE I. 
Fig. I. The basal part of an upright stem of Catamites , showing nodes with whorls of adventitious 
roots coming from the stem. The arrows indicate the position of the nodes. 
Fig. 2. Part of a tangential longitudinal section of a stem of Catamites (551 S), showing a root 
(r.) in approximately transverse section. /. A, leaf-traces ; i.n.o., infra-nodal organs; x., vascular 
bundles of stem ; m. r., medullary rays. 
Fig. 3. Another portion of the same section as that from which Fig. 2 is made, showing another 
root from the same node. x. x., two stem-bundles ; m. r. } medullary ray ; i. n. o., infra-nodal organ ; 
r. f root. 
Fig. 4. Another tangential section from the same block as Figs. 2 and 3. r. } root; i. n.o., infra- 
nodal organs. Slide 552 S. 
Fig. 5. Another section showing the same root. x. r., xylem of stem; x. r. t xylem of root; 
pith of root. Slide 553 S. 
Fig. 6. Radial section of a stem of Catamites also passing radially through a root, s., stem ; 
m.r., medullary rays of stem ; s.p., pith of stem ; r., root ; r.p., pith of root. Slide 11 M. 
