671 
1898-99.] Edith Chick on Eicinis Communis. 
Fig. 12. At 15 '5 cm., showing the first appearance of a, /3. 
Fig. 13. At 16 *5 cm., showing, between the cotyledon traces, the 6 groups 
of 3 epicotyledonary leaf traces each, which at a lower level unite to form the 
bundles a, b, c, d, etc. 
Fig. 14. At 18*5 cm., the cotyledon traces are passing off to the cotyledons, 
and semicircular groups of bundles, resulting from the division of a, 13, are 
passing off to the axillary bud on either side. The stele is now formed 
entirely of epicotyledonary leaf traces. The groups of 3 bundles between 
the cotyledon traces have divided more or less regularly, and the larger 
bundles are those which belong to the first pair of leaves above the cotyledons. 
Fig. 15. Diagram representing the branching and anastomosing of the 
cotyledon traces in the petiole as taking place in one plane, whereas the 
process occupies a length of several millimetres. 
Figs. 16-17 (a). Epicotyl. 
Fig. 16. Diagram of section at 19‘2 cm. above the e collet.’ The larger 
bundles are the traces of the next pair of leaves above the cotyledons. 
See plate I. for figs. 16a-21. 
Fig. 16 (a). Diagram of a slightly higher level. The traces belonging to 
the first pair of leaves have left the epicotyledonary stele. Those above the 
dotted line belong to one leaf, those below to the other. 
Figs. 17 and 17 (a). Diagrams of sections of the epicotyl about the level 
at which the first isolated leaf is given off. The traces leave the stele first on 
the side remote from the leaf, and form a girdle round the stem. The arrows 
in 17 (a) mark the position in the stele of leaf traces belonging to this leaf. 
Figs. 18-21. Diagrams of embryo. 
Fig. 18. Diagram of radial longitudinal section through growing point of 
embryo in the plane passing between the cotyledons, a. b. , median leaf traces 
of first pair of leaves; l.l., first pair of leaves; c.p., confluent bases of 
cotyledon petioles. 
Fig. 19. Diagram of transverse section of embryo at level C (fig. 18), 
showing a and b dying out in the hypocotyl. 
Fig. 20. Transverse section at level B (fig. 18), showing a and b cut 
obliquely and first appearance of c and d. 
Fig. 21. Transverse section at level A (fig. 18) ; the cotyledon traces are 
now in the petioles ; a and b appear as the only bundles as yet developed 
at this level of the first pair of leaves. 
Plate III. 
Fig. 22. Germinating Ricinus seed in which transverse sections of 
hypocotyl show 8 bundles only up to A. From A to B (2 mm. ) branching 
of bundles, as in fig. 8, takes place. 
The following sections are drawn with Abbe’s Camera under Zeis’s | in. : 
Fig. 23. Tangential longitudinal section through growing point of an 
embryo, showing at A the first appearance of one of the bundles, c, d, etc. ; 
l., first leaf ; c.p., cotyledon petiole base. 
Fig. 24. Transverse section of embryo hypocotyl in region where 8 
cotyledon traces only are found, showing one of the 8 traces; cor., cortex ; 
X., xylem ; P., phloem ; per., pericycle. 
Fig. 25. Transverse section root, showing fibres (/.) in the phloem in 
close connection with sieve tubes s.t. ; c.c., companion cells; end., endoder- 
mis ; per., pericycle. 
