322 Bower. — Studies in the Phytogeny of the Fiticales. 
Fig. io. Transverse section of a runner of Lophosoria , showing a leaf-trace being given off from 
the solenostele. Note that the separation of the two margins is not simultaneous. Slightly 
enlarged. 
Fig. n. (i-y.) A series of transverse sections through a runner of Lophosoria. (i) is the lowest/ 
and the series illustrates the successive stages of separation of a leaf-trace from the solenostele. In (v) 
the ring is again completely closed. Note that the leaf-traces in (i) and (iv) have their margins 
united to form a ring : this has only been observed in the traces of arrested leaves. Slightly 
enlarged. 
Fig. 12. (i-iii.) Successive sections from below upwards transversely through an axis of 
Lophosoria, showing the relation of the vascular supply of a runner to that of the axis and leaf, b 
indicates the runner itself, x 4. 
Fig* I 3* (i-iii.) Tangential sections through the base of insertion of a runner upon the leaf- 
base to which it is related, (i) shows the runner itself, with its solenostele ; (ii) shows the solenostele 
now connected with the leaf-trace, which being cut tangentially appears as a broad sheet of vascular 
tissue. Slightly enlarged. 
Fig. 13 bis. a , b. Transverse sections of the petiole of Lophosoria. a is from a point near the 
hase, and shows the trace divided into three strands, while opposite the gap between them there is 
on either side an interruption of the superficial sclerenchyma for ventilation purposes, b was taken 
at a point higher up, and the trace is here a single continuous strand, x 4. 
PLATE XXXV. 
Fig. 14. (i-vii.) Series of transverse sections of the rachis of Lophosoria , successively from 
below upwards, showing the origin of the pinna-trace, x 4. 
Fig. 15. (i-vii.) Series of transverse sections of the rachis of Gleichenia linearis , for comparison 
with Fig. 14, showing the origin of the pinna-trace, x 4. 
Fig. 16. Hairs from the sorus of Lophosoria , which are unbranched, and not obviously glandular, 
x 100. 
Fig. 17. Transverse section of the stalk of a sporangium, showing its relatively massive character, 
x 200. 
Fig. 18. Sporangium of Lophosoria presenting its ‘peripheral’ face, and showing that the 
annulus is uninterrupted and the dehiscence lateral, while the area surrounded by the annulus is very 
large, x 150. 
Fig. 19. A similar sporangium presenting its ‘ central ’ face, x 150. 
Fig. 20. A similar sporangium seen in lateral view, presenting the side which bears the stomium. 
The lower face, as seen in the drawing, would be opposite the surface of the leaf, x 1 50. 
Fig. 21. Section vertically through a very young sorus of Lophosoria , taken so as to include 
the margin of the pinnule, x 400. 
Fig. 22. Section of a similar sorus in a direction at right angles to that of Fig. 21. x 400. 
Fig. 23. Transverse section of a similar sorus. The cells marked x will produce sporangia, 
x 400. 
Fig. 24. Vertical section of a rather older sorus, in which the sporangia and hairs are becoming 
apparent, x 400. 
Figs. 25-7 . Longitudinal sections of young sporangia of Lophosoria , showing details of their 
segmentation, and the hairs which accompany them, x 400. 
Fig. 28. Vertical section through a young sorus of Lophosoria , so as to follow the course of the 
vascular strand which supplies the receptacle. Two sporangia are traversed, and many of the simple 
hairs, x 200. 
Fig. 29. A similar sorus cut transversely to the course of the vascular strand, showing three 
sporangia and the hairs as before, x 200. 
Fig. 30. Vertical section through a sporangium of medium age. x 200. 
Fig. 31. Transverse section through a sporangium of like age, showing the usual number of 
spore-mother-cells, x 200. 
Fig. 32. A similar section, showing the unusual number of nine, x 200. 
Fig. 33* Vertical section through an almost mature sorus of Lophosoria. The vascular supply 
into the receptacle is shown, and four sporangia, together with numerous hairs. The spores are still 
in tetrads. Note that the orientation of the outer two sporangia, as shown by the position of the 
