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SUMMARY OF CURRENT RESEARCHES RELATING TO 
Alkaloid-receptacles of the Fumariaceae,* * * § — Herr W. Zopf has 
investigated the chemical nature of the contents of the special receptacles 
of the Fumariaceae. He found the underground organs of Gorydalis cava 
to contain six different substances, viz.: — (1) a resin-acid soluble in 
benzol, (2) a resin-acid insoluble in benzol, (3) a yellow acid pigment 
soluble in water, (4) a yellow-green oil, (5) a special alkaloid, corydalin, 
(6) sugar. Of these substances, the one which is especially found in 
the idioblasts of tbe aerial organs is the alkaloid corydalin, which is 
replaced in Fumaria by fumariin, and in Dicentra , Adlumia , &c., by 
other special alkaloids. The alkaloids have their origin partly in the 
primary, partly in the secondary meristem. 
Latex-receptacles-t — According to Herr M. Debmel, latex-tubes are 
organs for the conduction of nutrient material, and are therefore nearly 
related to sieve-tubes. In the species of Compositae examined, all the 
Liguliferae contained latex, but none of the Tubulifiorae. 
M. Thouvenin J describes the laticiferous system in Cardiopteris 
lobata, belonging to the Olacaceae. In the stem the latex-tubes occur in 
the middle region of the cortex, in the liber, and in the periphery 
of the pith ; they are also found in the petiole and in the veins of the 
leaf. 
Sieve-fascicles in the Secondary Xylem of Belladonna.§ — Dr. G. 
Beauvisage states that the details of the anatomical structure of the roots 
of Atropa Belladonna have hitherto been only inadequately described. 
In the secondary tissues there is a somewhat abnormal structure 
analogous to that described in the stems of Stryclmos , which consists in 
the presence of numerous sieve-fascicles in the secondary xylem. In the 
case of Strychnos two modes of formation have been suggested, the one 
by De Bary, the other by M. Herail. After careful research the author 
finds that proposed by De Bary to be applicable to Atropa Belladonna. 
It is that the cambial zone, instead of giving rise, as is usual, to sieve- 
tubes without and vessels within, produces both on its internal face. 
Extra-phloem Sieve-tubes and Extra-xylem Vessels. || — M. P. 
Van Tieghem states that sieve-tubes can be formed outside the phloem, 
in the root, stem, and leaf. A lateral root of Strychnos nux-vomica has 
six phloem-bundles, and as many primary alternate xylem-bundles out- 
side the pith. At the periphery of the pith small bundles may be seen, 
which are composed of narrow sieve-tubes and parenchymatous cells ; 
these circummedullary sieve-bundles are formed at first in corre- 
spondence with the primary xylem-bundles. Sieve-tubes are occasionally 
found in the cortex of the stem, for example in Cucurbitaceae and 
certain Melastomaceae. The stem of Cucurbitaceae also has sieve-tubes 
in the pericycle. Vessels may be found outside the primary xylem also, 
in the root, stem, and leaf. Many Monocotyledons produce vessels in 
the pith of their roots larger than those which form the xylem-bundles. 
* Ber. Deutsch. Bot. Gesell., ix. (1891) pp. 107-17. Cf. this Journal, 1887, 
p. 427. 
t ‘ Beitr z. Kenntniss d. Milchsaftbeh'alter d. Pflanzen,’ Liegnitz, 1889, 46 pp. 
See Bot. Centralbl., xlvi. (1891) p. 385. 
X Bull. Soc. Bot. France, xxxviii. (1891) pp. 129-30. 
§ Joum. de Bot. (Morot), v. (1891) pp. 161—3. || Tom. cit., pp. 117-28. 
