ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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elements. They are always of secondary origin, springing from fully 
developed pith-cells. The passage of the bundles from the vascular- 
bundle system into the pith always takes place in the nodes ; the medul- 
lary bundles begin to be formed either in a node or in some one spot in 
an internode. Their presence is of no value for the classification of the 
group. 
Anomalous Stem of Thunbergia.* * * § — Prof. R. Chodat and M. C. Roulet 
describe the following anomalous structure in the stem of Tliunbergia 
laurifolia (Acanthaceae). The xylem consists of four arcs, two thinner 
and two thicker. In the two thicker arcs islands of parenchymatous and 
sieved xylem, elongated tangentially, alternate in the radial direction with 
lignified bands of woody fibres ; they are separated from one another by 
lignified vascular xylem. The two thinner arcs acquire this structure 
only at a later period. According to the authors, these islands of sieve- 
tubes are bands of sieved xylem, like those of Dicella , and the generating 
layer is continuous ; the pericycle takes no part in the formation of the 
uniting tissues. Hexacentris coccinea has a similar structure. 
(4) Structure of Organs. 
Archegone and Apical Growth of the Stem in Coniferae.f — Mr. D. 
M. Mottier has investigated these points of structure in Tsuga canadensis 
and Pinus sylvestris. He finds the neck of the archegone (corpuscle) to 
consist, in Tsuga , frequently of two, and occasionally of three cells; in 
Pinus sylvestris the cells of the neck form two layers instead of one. 
With regard to the apical growth of the stem in both species, his 
observations lead him to the conclusion that we cannot say with certainty 
that there is a single cell at the apex of the stem, unless it be in the stem 
of the young plant, and even then it is not absolutely certain. 
Anthocyanic Flower of the Carrot.t — Dr. M. Kronfeld describes 
under this term the central coloured flower in the umbel of Daucus 
Carota, the red colour of which is due to the presence of anthocyan in 
the petals, and also frequently in the stamens, nectary, and ovules. The 
petals are larger, and are recurved inwards, and the filaments are also 
curved inwards, as is their ordinary position in the bud. In opposition 
to the usual statement, Dr. Kronfeld asserts that the anthocyanic flowers 
are usually hermaphrodite, less often female, and that they are generally 
fertile. He believes them to be cleistogamous and self-fertilized. 
Fruit and Seed of Eugenia.§— Dr. E. Baroni describes in detail the 
anatomical structure of the fruit and seed of Eugenia myrtillifolia 
(Myrtaceae). Besides chlorophyll, the seeds contain a colouring matter 
allied to anthocyan, tannin, starch, sugar, and essential oils. 
Borragoid of the Borraginace3e.||— Herr K. Schumann points out 
that the peculiar inflorescence of the Borraginaceas, to which he has 
applied the term “ borragoid,” and which attains its fullest development 
in Anchusa, is merely an extreme case of the extra-axillary inflorescence 
* Arch. Sci. Phys. et Nat., xxvii. (1892) pp. 27-9. 
t Bot. Gazette, xvii. (1892) pp. 141-3 (1 pi.). 
X SB- K. K. Zool.-Bot. Gesell. Wien, xli. (1891) pp. 83-4. 
§ Bull. Soc. Bot. Ital., i. (1892) pp. 275-83. 
|| Bcr. Deutsch. Bot. Gesell., x. (1892) pp. 57-63 (1 fig.). 
