138 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
(4) Structure of Organs. 
Anatomy of Loranthaceae.* — Mr. F. W. Keeble calls attention to 
the following anatomical details in the Cingalese Loranthaceae. In 
Loranthus neelglierensis the hypocotyl of the fully developed embryo is 
densely covered with green columnar emergences, the cortical cells of 
which contain chlorophyll, starch, and tannin. A single stomate occurs 
on the free surface of each emergence. In this species there is not, as 
in most, a well-developed suctorial disc at the free end of the hypocotyl, 
the sucker obtaining entrance in another way. 
Floral Leaves without Vascular Bundles.f — H. P. van Tieghcm 
applies the term meristele to the branch of the cauline stele which 
enters the lamina of the leaf, and there branches into the veins. He 
further states that the non-ovulate orders of Phanerogams comprised in 
the LoranthineaB, which exhibit such remarkable simplicity of structure 
in other ways, are further characterised by a frequent entire absence of 
meristele in the foliar leaves ; these being then reduced simply to cortex 
and epiderm. In the majority of the dicblamydeous families, the 
Loranthaceae, &c., this is the case with the sepals. In those in which 
the corolla is wanting, the Viscaceae and the Arceuthobiaceae, the calyx 
is not reduced to this simple condition, but reduction is frequently 
presented by the stamens. In the Arceuthobiaceae and Balanophoraceae, 
again, the carpels present a similar simplicity of structure, being 
entirely destitute of meristele. 
Variation in Flowers of Salix.J — Dr. W. Haacke has studied the 
variations which occur in the groups of catkins borne by branches of 
Salix caprea when the undergrowth of the tree has been cropped for 
years. The main catkin of a group gives up its female character much 
less frequently than the accessory catkins, and the apex of the catkin 
loses its female character much more readily than the other part. Both 
facts are explained as due to differences of position in relation to nutritive 
supply. From the fact that definite forms, e.g. male flowers, occur at 
definite places, Dr. Haacke argues in favour of the definiteness of organic 
reactions. 
Protection of Pollen from Rain.§ — Prof. A. Hansgirg classifies 
under four types the flowers in which the pollen is protected against rain 
by phytodynamic contrivances, viz.: — (1) Flowers which close their 
perianth in rainy weather, so as to prevent the entrance of rain-drops 
without changing the position of the flower-stalk or stalk of the in- 
florescence. (2) Flowers with erect flower-stalks, which curve in rainy 
weather so as to alter the position of the opening of the corolla and pre- 
vent the access of rain to the pollen and nectar. (3) Flowers in which 
a curvature of the axis or stalk of the inflorescence serves the same 
purpose of protecting the flowers against the access of rain. (4) Flowers 
which are erect and open in fine weather, but, during rain, both close 
their perianth and at the same time protect the pollen by a curvature of 
the flower-stalk. 
* Ann. Bot., x. (1896) pp. 626-7. 
t Rev. Gen. de Bot. (Bonnier), viii. (1896) pp. 481-90. Cf. this Journal, 1896, 
p. 327. X Biol. Centralbl., xvi. (1896) pp. 817-25 (8 figs.). 
§ Oesterr. Bot. Zeitscbr., xlvi. (1896) pp. 357-8. 
