90 F. J. F. Shaw. 
A series of longitudinal sections cut at right angles to the plane 
of the ovules affords a complete confirmation of the interpretation 
advanced above. Such a series is of course tangential to the main 
bundle. The sections begin on the side farthest from the sterile 
ovule—hence we gradually cut through the main bundle and into 
the “horns.” In Text-fig. 17, 12 the main bundle is shewn, flanked 
by two others with inverted orientation. Further across the main 
bundle the plane of section traverses the region where it is passing 
into the concentric state. A section here shows the main bundle 
with two lateral anomalous bundles; the cambium, however, is 
continuous, the latter appearing as wings of the former (Text-fig. 
17, 13 ); all the tracheids run longitudinally. Here is seen the first 
indication of the gutter of cambium, filled, of course, with phloem, 
as described above. In the succeeding sections, approaching the 
sterile ovule, the distance from the top of the main bundle to the 
bottom of the gutters decreases, this shows that the gutters are 
running obliquely upwards through the collar (Text-fig. 17, 14 and 15 ). 
Text-fig. 17. Longitudinal sections (tangential). 
12, 13, 14. Sections passing through main bundle towards sterile ovule— 
cambium of main bundle continuous with that of anomalous tissue. 
15. Tracheids of anomalous tissue and those of main bundle at the 
“ horns ” cut transversely. 
16. Union of “horns”—above, the main bundle is giving rise to one of 
the smaller concentric bundles in the ovule. 
