Female Flower of Juglans regia and a feiv allied Genera . 627 
It is through this tissue that he succeeded in showing that the pollen- 
tube made its way to the chalaza of the ovule. 
The upwardly running series of cells of this packing tissue are those 
referred to by E. M. Kershaw 1 as £ an obturator \ In all the specimens we 
have seen they are so closely attached to the ovarian wall that they appear 
as represented in Text-fig. IV. 1 and 2. 
They are attached to the middle region of the low septum made by the 
junction of the two placentae, and are seen in transverse section in Text- 
fig. II. 2. 
Their form and height in longtitudinal sections depend on the plane in 
Text-fig. IV. i, 2, Juglans regia. Two diagrams rom longitudinal sections to explain the 
relation of the packing tissue (p>) and the ovule. 1. Lies in the median plane through the midribs 
of the two carpels. 2. Is oblique, to illustrate the limited extent of the upwardly running packing 
tissue (/). These two diagrams should be compared with Text-fig. II. 2 and Text-fig. III. 1. 
cb — cupule bundles, d — dorsal bundles of carpel, p = packing tissue, pb = perianth 
bundles, s = septum. 
which they are cut. They disappear in radial sections in the antero- 
posterior plane of the flower (Text-fig. III. 1). 
The packing tissue in the ovary of Juglans appears to be comparable 
morphologically with the hairs borne on the placentae and funicles of the 
ovules of Populus and Salix, although in these genera the growth subserves 
a different function. 
If we turn now to the diagrams from radial sections of the flower we 
see in Text-fig. III. 2 the source of the placental bundles. They have no 
direct representatives in the axis, as Nicolofif claims, but are built up from the 
leaf-traces given off at the base of the flower to the carpels. This fact is 
demonstrated by radial sections in the plane of the two styles. The bundles 
in question travel horizontally until they reach the centre of the flower. 
Their subsequent course is shown in Text-fig. III. 1, which is a diagram from 
an almost radial section in the lateral plane of the flower. Van Tieghem 2 
explains this course as follows : — ‘ Le faisceau descendant destine a l’ovule 
forme d’abord un assez long funicule qui demeure compris dans le paren- 
chyme du bord fertile.’ He thus claims that not only is the ovule 
1 E. M. Kershaw, Annals of Botany, April, 1909, p. 337. 
3 Van Tieghem, loc. cit. 
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