ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
47 
pericyclic. At each outward displacement of the layer outside the 
vascular bundles, there takes place, within and without each phloem 
island, a kind of doubling of the generating zone, whatever its origin. 
The course of the foliar bundles is in a wavy line, each bundle 
continuing through a space of three internodes before passing into 
the leaf. 
Stem of Scorzonera. * — Herr A. Peter describes the anatomical 
structure of the stem of Scorzonera , and classifies the species under 
groups, characterised by differences in the disposition and structure of 
the vascular bundles. This does not always go along with an arrange- 
ment of the species derived from morphological characters. 
Conversion of Cellulose into Mucilage.| — Herr 0. Rosenberg has 
studied the formation of the layer of mucilage in the seeds of Magonia 
glabrata , belonging to the Sapindace®. It differs from that of other 
mucilaginous seeds in the fact that it is derived, not from the lower or 
the lateral walls of the epidermal cells, but from a layer underlying 
the epiderm. The mucilage-tissue in the seed differs but little from 
that in the leaf. The object of the structure appears to be, by the 
absorption of water, to protect the embryo from desiccation. 
C4) Structure of Organs. 
Female Flower and Inflorescence of Cannabinese.J — Herr N. Z winger 
has studied in detail the structure of the female flower and the mode of 
fertilisation in Cannabis , Humulus, and allied genera. 
In the hemp the female flowers are not associated in an inflorescence, 
but are solitary in the axils of the bracts on branches of various orders. 
In Rnmulus there occur transitional conditions from the solitary position 
in Cannabis to the inflorescence of the hop. The bracts of the female 
plants of Cannabine® are the leaves in whose axils the flowers are 
formed. The perianth of the female flower is composed of two inde- 
pendent leaves ; in the hemp it is often entirely aborted, or the posterior 
leaf only is developed. The pistil is formed from the floral axis as 
well as from the two carpellary leaves ; but it is only the anterior leaf 
which takes part in the formation of the wall of the ovary, while the 
other leaf forms simply the posterior part of the style. The ovule, 
as in most Monochlamyde®, is formed from the apex of the floral axis ; 
the elevated position of the ovules in the upper part of the ovary is 
due to the elongation of the internode which separates the two carpels. 
The two integuments coalesce with one another from the posterior 
side of the ovule. 
When the ovule is ready for impregnation, the micropyle has become 
entirely obliterated. When the pollen-tube has penetrated the style, 
it makes its way within the tissue of the ovule, and finally reaches the 
nucellus ; thus presenting a close analogy to the chalazogamy of the 
elm. The placentation of the Cannabine® indicates that they cannot 
be descended from porogamous plants. 
* Nachr. k. Gesell. Wiss. Gottingen, 1898, pp. 9-20. 
t Bill. k. Svensk. Vetenslc.-Akad. Handl., xxiii. (1898) Afd. 3 (18 pp., 1 pi., 3 figs.) 
German). % Flora, lxxxv. (1898) pp. 189-253 (5 pis., 2 figs.). 
