RS ee ae RENE EOE MENS eb eT eS fae TEM eee eee oem es ery 
1909] CURRENT LITERATURE 319 
questionable validity in the light of OsteRHovtT’s researches in this line.3?— 
Anatomy of the ovule of Myrica.—Miss KersHAw:% has investigated the 
ovule of Myrica Gale, and has discovered that in all of the morphological features 
itis an ordinary angiosperm, with its solitary megaspore mother cell, linear tetrad, 
eight-nucleate embryo sac, and porogamy. The following anatomical features, 
Owever, are worthy of mention: the nucellus is not only completely free from 
the single integument but is also distinctly stalked within it; vascular strands 
(eight or nine in number) traverse the integument, without branching, almost to 
the apex of the ovule. These two features of the ovule are usually regarded as 
primitive, belonging to the ancient gymnosperms rather than to angiosperms.— 
oom. C, . 
Phototropism of roots.—LINSBAUER and VOUK, after overcoming many 
experimental difficulties, have found3+ that the roots of Raphanus sativus and 
Sinapis alba, which have been credited with being only negatively phototropic, 
Teact positively or negatively according to the intensity of the light. Roots of the 
ormer in moist air turn toward light of about 8 candles, while in water they are 
much less sensitive, no very certain curvatures being obtained until the light was 
increased to 400 c.p. Sinapis in water, on the contrary, gave the best positive 
response at o.2 c.p., and decided negative curvatures at 0.64 ¢.p. These results 
Support the M@LLER-OLTMANNS theory of phototropism.—C. R. B. 
Dispersal of seeds by ants.—Werss%5 has concluded that the gorse (Ulex) and 
the broom (Sarothamnus) should be included among myrmecochorous plants, 
along with Chelidonium, Viola, etc. He finds that the seeds have a brightly 
colored caruncle containing oily food material and resembling in structure and 
contents the elaiosomes (of SERNANDER) of other myrmecochorous plants; that 
ants are particularly attracted by the oil-containing caruncle, and can and will 
carry about the seeds of gorse; and that the rectilinear distribution of gorse 
bushes along actual or disused paths or roadways is only paralleled by the distri- 
bution of such plants as the celandine along ant-runs.—J. M. C. 
Anatomy of Gleichenia. —BoopLE and Hitry*° have investigated the vascular 
Structure of Gleichenia, a genus interesting on account of its protostelic species. 
— 
% Bor. Gazetre 46: 53-55. 1908. 
Be Kkisuiw Eos Mav, The structure and development of the ovule of Myrica 
Gale. Annals of Botany 23:353-362. pl. 24. 1909. 
SBAUER, K., anD Vouk, V., Zur Kenntnis des Heliotropismus der Wurzeln. 
ch. Bot. Gesells. 27:151-156. 1909. 
_ °*5 Weiss, F. F., The dispersal of the seeds of the gorse and the broom by ants. 
New Phytol. 8:81 
34 LIN 
Ber. Deuts 
—89. Igo9. 
a * Boopte, L. A., AND Hixey, W. E., On the vascular structure of some species of 
leichenia, Annals of Botany 23:419-432. pl. 29. 1909. 
