ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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verse section. In the parenchyme of the stalk are clusters of crystals 
of calcium oxalate united to the cell-wall by bands of cellulose. In the 
tissue of the projections which occur on the surface of the ripe inflores- 
cence are collencliymatous cells, and between them a number of inter- 
cellular spaces, in which are roundish or sharp outgrowths from the 
cell-wall, similar to those found in the roots of Orchideee. 
(4) Structure of Organs. 
Flower of Cruciferse and Fumariacese.* * * § — On anatomical grounds 
M. 0. Lignier comes to the following conclusions with regard to the 
composition of the flowers of Cruciferae. The petals are simply lateral 
lobes of leaves, of which the sepals are the median lobes ; while the six 
stamens correspond to two three-lobed leaves. The structure of the 
flower is therefore closely analogous to that of Fumariaceae, except that 
the anterior and posterior sepals of the latter are wanting in Cruciferae. 
The floral formula is S 2 (S -f- P) 2 St 2 C 2 . 
With regard to the flowers of Fumariacese, M. Lignier adopts the 
view that each bundle of stamens in this order represents a three-lobed 
leaf. The flower is then composed of five alternate whorls of opposite 
leaves, corresponding to the formula S 2 P 2 + 2 + St 2 C 2 , the members of 
each whorl exhibiting a tendency to trilobation. In Hypecoum the two 
staminal leaves are strongly connate. 
Dimorphism of Convolvulus.')' — Sig. O. Massalongo gives further 
illustrations of the heterandry in the stamens of Convolvulus arvensis 
produced by the attacks of Thecaphora Convolvuli , which, however, he 
identifies with C. hyalina. The same fungus attacks also the flowers of 
C. sepiurn and C. Soldanella. 
Pollen-Grains.J — Mr. J. E. Walter gives descriptions and drawings 
of the pollen-grains of about 120 species of American plants belonging 
to the Dicotyledones. 
Monopodial Ramification of Carex.§ — Mr. T. Holm points out the 
frequent occurrence of monopodial ramification in American species of 
Carex. In the monopodial species the floral shoots are surrounded at 
their base by scale-like leaves; while in the sympodial species the 
flowering stems are commonly, if not always, surrounded by normal 
leaves with closed sheaths and long green blades. 
Heterocarpy.il — Herr E. Huth enumerates further examples of 
different forms of fruit found on the same species, especially of the kind 
which he terms heteromericarpy , in which the two halves of a binary fruit 
differ from one another. This occurs in Turgenia heterocarpa and in 
many other Umbelliferae, also in Cruciferae, and occasionally in 
Commelyna , Valerianella, Antirrhinum , and Nigella. Macleya cordata 
(Papaveraceae) presents two forms resembling one another completely 
* Comptes Rendus, cxxii. (1896) pp. 630-2, 675-8. 
t Bull. Soc. Bot. Ital., 1896, pp. 11-3. Cf. this Journal, 1895, p. 549. 
I Observer (Portland, Conn.), vii. (1896) pp. 21-6, 59-63 (2 pis.). 
§ Amer. Journ. of Sci., i. (1896) pp. 348-50 (1 pi.). 
|| Abhandl. u. Vortr. a. d. Gesammtgeb. d. Naturw., iv. (1895) 32 pp. See Bot. 
Centralbl., lxvi. (1896) p. 96. Cf. this Journal, 1891, p. 491. 
