ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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contrary, the green petals absorb oxygen and give off carbonic acid. The 
author inclines to support Pringsheim’s theory of the protective function 
of chlorophyll. 
Epiphyllous Flowers of Chirita hamosa.* — Herr C. E. Boldt has 
studied the peculiar phenomenon in this plant, belonging to the Cyrtan- 
drese, and concludes that it results from the complete coalescence of a 
compound inflorescence with the tissue of the leaf. The similar epi- 
phyllous inflorescence of Streptocarpus and other genera of Cyrtandreae is 
certainly axillary and not adventitious. 
Pistil and Fruit of the Caprifoliacese.f — M. L. Vidal describes in 
detail the difference of the structure of the pistil and the fruit in the 
two tribes of this order, the Sambuceae and the Lonicereae. In the 
Sambuceae the ovary is only partially inferior, the style is short, with a, 
large canal, the stigma is lobed, and the fruit a drupe. In the Lonicereaa 
the ovary is completely inferior, the style long, and the canal obliterated, 
the stigma entire, or nearly so, the fruit a berry, capsule, or drupe. He 
further proposes the division of the Sambuceae into two groups, the 
Eusambuceae ( Sambucus , Adoxa), and the Viburneae ( Viburnum ), which 
presents an approach to the Lonicereae ; also of the Lonicereae into two 
groups, the Eulonicereae, in which the fruit is a berry, or a capsule 
with multiovular loculi, and the Linnaeeae, in which the fruit is a drupe, 
either uniovular or multiovular. 
Dichroism in Plants.^ — Prof. F. Delpino records a number of 
examples of a variation of colour in the same species unaccompanied by 
any anatomical difference : — Euphorbia Peplis, stem and leaves red or 
yellow ; Anagallis arvensis , flower scarlet (var. phoenicea ) or blue (var. 
coerulea ) ; a similar variation in A. collina ; in the colour of the flower 
in Orchis provincialis (Liguria), 0. sambucina, Erica arborea (Tuscany), 
and Thalictrum a quilegi folium ; Solatium nigrum , berries black or yellow 
( S . miniatum ), &c. In some cases the difference is probably connected 
with the piomotion of cross-pollination. 
Adaptation of Land-Plants to existence in Water. § — Dr. R. Keller 
describes the changes in external habit, and in the structure of its tissues, 
undergone by Myosotis palustris when growing submerged in water. The 
lower stem-nodes produce roots, the lowermost of which branch, but there 
are no root-hairs ; the stem becomes nearly round ; the leaves are 
narrower and thinner. This is accompanied by differences also in the 
anatomical structure : — the conducting system is reduced ; the epiderm 
and cuticle are reduced in thickness. 
Extra-Floral Nectaries. || — Herr V. A. Poulsen describes several 
fresh examples of these structures from Java. In Excoecaria biglandu- 
losa there are on the leaf-stalks two conical projections, hypodermal 
* Yidensk. Mecld. Naturhist. Foren. Kjobenhavn, 1897 (10 figs.). See Bot. Cen- 
tralbl., lxxiv. (1898) p. 128. 
t Ann. Univ. Grenoble, 1897, 19 pp. and 3 figs. See Bull. Soc. Bot. France, xliv. 
(1898) p. 522. 
X Bend. B. Accad. Sci. Napoli, 1897, 6 pp. See Bot. Centralbl., lxxiv. (1898) 
p. 51. § Biol. Centralbl., xviii. (1898) pp. 241-5 (6 figs.). 
||| Yidensk. Medd. Naturhist. Foren. Kjobenhavn, 1S97, pp. 356-71 (3 pis.). See 
Eot. Centralbl., lxxiii. (1898) p. 454. 
