ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
61 
Sac-cells of Fumariaceae.* * * § — Commenting on Zopf’s most recent 
researches on the structure and contents of the idioplasts in Corydalis 
and other Fumariaceae, Herr E. Heinricher repeats the assertion that 
their most important contents are an oil mixed with other substances, 
tannin and anthocyan being found in them only exceptionally. 
Spicular Cells of Welwitschia.j - — Herr C. Bleiscli gives details of 
the structure of the well-known spicular cells of WelwitscMa, which 
are encrusted with calcium oxalate, and of similar idioblasts which 
are found in certain Coniform and Nymphaeaceas. They all have a 
strongly thickened wall, the outer layers of which show the reactions 
of lignin, the inner layers those of pure cellulose. The crystals are 
imbedded in a special layer of the cell-wall, which appears to consist of 
a substance intermediate in composition between cellulose and oxalic 
acid. 
Primary Structure and Affinities of Pines.l — H. P. Yan Tieghem 
thus sums up the results of his observations on this subject. The root 
of pines contains vascular bundles of normal form, opposite each of 
which a deep layer of thick pericycle produces a secretory canal. The 
non-specialized region of the stem has only pericyclic secretory canals 
superposed to the bundles, and the leaves of this region have only 
cortical secretory canals, normally one on each side. The specialized 
region of the stem has sometimes the same structure, but more often 
it acquires secretory canals in the primary xylem of the bundles. Iu 
this case the short branches and their green leaves are most frequently 
destitute of these secretory canals in the xylem. In the arrangement of 
the secretory apparatus Pinus more resembles Picea, Larix, and Pseudo- 
tsuga, than Abies, Tsuga, Cedrus, and Pseudolarix. In their structure 
Picea differs from Abies, Larix from Pseudolarix , and Pseudotsuga from 
Tsuga, more than is generally supposed. 
Structure of Memecyleae.§ — From a careful study of the structure 
of all the genera of this family and of that of 130 out of the 135 genera of 
typical Melastomacem, M. P. Van Tieghem concludes that the Meme- 
cylem should be regarded as a tribe of the Melastomaceas distinguished by 
having the phloem inclosed in the secondary xylem. They are again 
divided into two families, the Mouririese ( Memecylon , Mouriria) with, 
and the Pternandrene (Pternandra, Kibessia, Pectomitra), without 
sclerites. The remaining genera of Melastomacete, constituting the tribe 
Melastomese, with normal secondary xylem, may be arranged under four 
families, according as there are supernumerary vascular bundles iu the 
cortex only, in the pith only, in both, or in neither. 
Anatomy of the Epacridacese and Ericaceae. || — Herr F. Simon com- 
pares the minute details of structure in the plants belonging to these two 
* Ber. Deutscli. Bot. Gesell., ix. (1891) pp. 18i-7. Cf. this Journal, 1891, p. 618. 
t ‘ Zur Kenntn. d. Spicularzellen .... d. Welwitschia,' 50 pp. and 1 pi, Strehlen, 
1891. See Bot. Centralbl., xlvii. (1891) p. 312. 
t Journ. de. Bot. (Morot), v. (1891) pp. 265-71, 281-8. 
§ Ann. Sci. Nat. (Bot.), xiii. (1891) pp. 23-92 (1 pi.), and p. 374. 
|| ‘"Beitr. z. vergleieh. Anat. d. Epacridacese u. Ericaceae,’ Berlin, 1890. See Bot. 
Centralbl., xlvii. (1891) p. 313. 
