98 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
its parts being arranged in whorls of three only, and the gynseceum 
being superior and apocarpous. 
Morphology and Anatomy of Obolaria.* * * § — Mr. T. Holm gives an 
account of the structure of this anomalous genus, which he places in the 
Gentianacese. It appears to occupy an intermediate position between 
autophytes and saprophytes. It has no primary root nor root-hairs, and 
is deficient in stereome; but, on the other hand, it has lignified tissue, 
as well as chlorophyll and stomates. It resembles Pleurogyne in having 
the inner surface of the carpels entirely covered by ovules. 
Morphology of Ilex and Cakile.f — Dr. M. Dalmer points out that 
in the holly, as in other spiny plants, the spines on the margins of the 
leaves are much more strongly developed on old than on young plants, 
and more so on lower than on higher branches ; indicating that their 
main function is probably protection against destructive animals. 
In Cakile maritima the peculiar umbrella-like arrangement of the 
branches appears to act as a protection against violent winds. 
/3. Physiology. 
(1) Reproduction and Embryology. 
Fertilisation. — Prof. E. Strasburger f discusses and compares the 
results obtained in connection with the reduction in the number of 
chromosomes which accompanies an act of conjugation or impregnation. 
In Bryophytes, Pteridophytes, and Phanerogams, the reduction-process 
coincides with the alternation of generations, and appears to present a 
typical form. In all Archegoniatae, Bryophytes, and Pteridophytes, the 
true generative division is that which takes place immediately before 
impregnation in the central cell of the archegone, producing the so-called 
ventral-canal-cell and the oosphere. 
Commenting on Strasburger’ s various papers on karyokinesis, Herr 
W. Belajeff§ charges him with confusing between fission and separation 
of the segments. The true fission of the segments takes place in the 
knot-stage ; that which is termed fission in the metakinesis stage is not 
in reality true fission, but is a separation of previously split segments. 
Fertilisation of Zamia and Salisburia.|| — Mr. H. J. Webber gives 
further details of the structure and action of the antherozoids of Zamia. 
For a considerable time during the development of the pollen-tube 
apparatus, the archegone remains in nearly the same stage of develop- 
ment, gradually increasing in size. During this period the very large 
nucleus remains at the apex of the archegone. Shortly before fecundation 
this nucleus divides, and a small cell is cut off at the apex, correspond- 
ing to the canal-cell of Conifers. The lower nucleus, which forms the 
oosphere, then travels downwards to below the middle of the archegone. 
Only one of the antherozoids takes part in the fecundation. It would 
appear that shortly after the antlierozoid enters the protoplasm of the 
archegone, the nucleus escapes from the body of the antherozoid and 
* Ann. of Bot., xi. (1897) pp. 369-81 (1 pi. and 1 fig.). 
t Bot. Centralbl., lxxii. (1897) pp. 6-13. 
X Jahrb. f. wiss. Bot. (Pteffer u. Strasburger), xxx. (1897) pp. 405-22. 
§ Ber. Deutsch. Bot. Gesell., xv. (1897) pp. 345-9. 
|| Bot. Gazette, xxiv. (1897) pp. 225-35 (1 pi.). Of. tliis Journal, 1897, p. 554. 
