Note especially that the tusk of the upper jaw grows upward from the
first. No part of it is directed into the mouth. This tusk is of
extraordinary size, and it curves upwards so as to touch, and sometimes
even to pierce, the skull. They are, as compared with those of other
swine, slender tusks, more especially the under ones. The upper tusk
grows through the skin of the upper lip. In old animals, when it is
well curved, it must be useless as a weapon. It may serve to protect
the eyes when the animal rushes through brushwood. In the female the
tusks are small.
* * * * *
ANSWERS TO CORRESPONDENTS, &c.
CONCHOLOGIST.--Your shells are _Helix nemoralis_ (immature), _Hyalinia
(Vitrea) pura_, and _Buliminus obscurus_. _Vitrea pura_ is a much
smaller shell than _V. nitidula_, the latter may be distinguished from
_V. radiatula_ by the striæ not being continued from whorl to whorl.
_B. obscurus_ is much smaller than any member of the genus _Clausilia_.
If you examine in May the trunks of beech trees growing on calcareous
soils you will find _B. obscurus_ and _Clausilia laminata_ ascending
them in large numbers to spend the summer aloft, coming down again in
October to go into hybernation at the base of the trees during the
winter months. You will find _C. rugosa_ (in modern terminology, _C.
bidentata_) equally common on the trees, it is smaller and thinner than
_C. laminata_. _B. obscurus_ is a short, stout little shell, seldom
exceeding 9 millimetres in height.
GARDENER. _Diseases of the Cultivated Chrysanthemum._--At the present
time three diseases are recorded for this country, viz., sclerotium
disease (_Sclerotinia sclerotiorum_, Massee); corticium disease
(_Peniophora chrysanthemi_, C. B. Plowright), and the only too familiar
Rust (_Puccinia hieracii_, Mart). The sclerotium, which first appears
as a white mould on the stem just above the ground, forms black lumps
within the stem. The stem becomes very brittle and falls. From the
black nodules in the following spring, small funnel-shaped brownish
fungi with long, weak, dark stems appear. The spores from these settle
upon dead organic matter, forming an abundant mycelium which ultimately
attacks the base of the stems of chrysanthemums. It is said that fresh
stable manure favours the spread of the disease. Diseased stems should
be carefully collected and burnt.
The corticium disease also appears on the lower part of the stem,
forming a white growth in autumn; Dr. Plowright, who first discovered
it, says it resembles a splash of whitewash. It is not confined to the
stems but extends into the adjacent soil. Diseased plants are shorter
in height and thinner in the stem than healthy; they always die within
the year. This disease has hitherto been observed only at King’s Lynn
in Norfolk, but it is very possible it occurs in other parts of the
country. Dr. Plowright remarks that the only treatment is burning the
diseased plant. It is useless to separate the apparently healthy shoots.
The well-known chrysanthemum rust first appeared in 1897, and spread
with great rapidity in the very dry summer of 1898. The snuff-coloured
uredo spores (summer form) are familiar to all cultivators of
chrysanthemums. This fungus occurs on many wild plants of the order
_Compositæ_, notably the hawk-weeds (_Hieracium_). All diseased plants
should be burnt. The disease may be prevented by spraying the new
leaves with potassium sulphide solution.
It is to be hoped that the chrysanthemum leaf blight (_Cylindrosporium
chrysanthemi_), which has caused so much damage to cultivated plants
in Ontario, Canada, will not find its way into this country. It forms
large dark patches on the leaves, which turn yellow and hang down; the
flower buds do not expand. It is stated that fungicides are useless.