228 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 
Moisture, Movement and Distribution of, in the Soil. By F. S. Harris and 
H. W. Turpin (Jour. Agr. Res. x. pp. 113-156, July 1917 ; 31 figs.). — The 
authors state that during recent years great differences of opinion exist as to the 
importance of soil capillarity of moisture and the laws governing the final dis- 
tribution of moisture in the soil. As a result of several thousand moisture 
determinations conducted under the varying conditions of moisture, and with 
fallow, manure, surface mulches, crops, irrigation water, cultural methods, and 
seasonal conditions in the field, the authors arrived at the following conclusions : 
the moisture content of fallow averaged higher than that of cropped soils, but 
irrigation influenced the top surface of cropped plots more than the top surface 
of the fallow. Water did not appear to penetrate the fallow plots below 7 feet 
as readily as it did in the cropped plots. Wheat, maize, potatos, and peas 
drew the greater part of their moisture from the first 4 feet in depth. 
The increase in moisture due to 5 to 7 5 inches of irrigation water was felt 
at depths of 10 feet in twenty-four hours, although most of the increase was in 
the first 4 feet. Mulches prevent the loss of water under both irrigation and dry 
farming to several feet of soil, though the surface foot is mostly affected. 
Sand containing 7-77 per cent, of water gave up its moisture to loam more 
readily than did loam with 31-00 per cent, of water, or clay with 24-62 per cent, 
of water. 
Water rose to a height of over 30 inches in a loam soil from a moist sand in 
ninety-four days, while from a clay soil it rose little more than 6 inches during 
a similar period. 
A short bibliography is appended. — A. B. 
Mutants of the Oenotheras, New Dimorphic. By Hugo De Vries (Bot. Gaz. 
vol. lxii. Oct. 1916 ; 5 figs.). — Besides Oenothera scintillans, which splits under 
ordinary circumstances in every generation into nearly equal groups of plants 
of the same type and others of the type of 0. Lamarckiana, De Vries has culti- 
vated pedigree families of four other mutants of O. Lamarckiana, which behave 
in the same manner. They are designated as 0. cana, 0. pallescens, 0. Lactuca, 
and 0. liquida. Their Lamarckiana-like offspring are constant in their progeny. 
Besides the two main types, they produce, as a rule, a relatively high percentage 
of other mutants. 
The parental type is on the average reproduced in about 40 per cent, of the 
seedlings, the other 60 per cent, being Lamarckiana, with some mutants ; but 
these figures vary considerably. 
In the dimorphic mutants, the special characters are handed down to the 
next generation through the ovules only. The pollen lacks these characters, 
and is, as far as investigated, not different from that of pure O. Lamarckiana. 
De Vries concludes that the dimorphic mutants constitute a group in which 
the hereditary phenomena are evidently independent of the external visible 
characters of the special members of the group, but that they must be assumed 
to have the same intrinsic causes in the different cases. — R. J. L. 
Narcissus, Investigation of Bulb Rot of Narcissus. Part I. The Nature of the 
Disease. By E. J. Welsford (Ann. Appl. Biol. iv. p. 36 ; Sept. 1917)- — Various 
organisms found in unhealthy bulbs were isolated and infection experiments 
carried out, but the disease, the symptoms of which are fully described on p. 51 
of this Journal, was reproduced only by infection with the stem eelworm, Tylen- 
chus devastatrix. A review of some of the literature of this pest is given, and 
special reference is made to Ritzema Bos's work on the Hyacinth rot, which is 
essentially similar to this, and which he called la maladie annulaire. The author 
recommends that weeds should not be allowed to wither on the ground which it 
is intended to replant with Narcissi, nor should they be dug in ; Narcissi should 
not be planted where eelworm-infested Narcissi have grown ; only healthy bulbs 
should be planted ; bulbs that fail to grow should be dug up before they rot ; 
bulbs with crinkly foliage should be burnt ; dying foliage should be collected 
and burnt. F- /. C. 
Nectar Secretion, Environmental Influences on. By Leslie A. Kenoyer 
(Bot. Gaz. vol. lxiii. No. 4, April 1917, pp. 249). — This is an account of the 
investigations undertaken to summarize and supplement existing knowledge 
of the factors which stimulate or retard the secretion of nectar. The effects of 
humidity, water supply, temperature, atmospheric pressure, and light are dealt 
with. The general conclusion arrived at was that the more favourable all 
conditions for growth and the more vigorous the plant, the greater is the amount 
of sugar secreted. Nectar is most "abundant early in the blooming season, 
other things being equal ; and accumulation and secretion of sugar is most 
pronouuced near the time of the opening of the flowtr. — R. J.L , 
