EEI’OET ON ECONOMIC ENTOMOLOGY 
247 
It is probable that in this country, the intermediate host-plant is dispensed with, as it 
has been proved that the sporidia from teleutospores are capable of directly infecting wheat 
seedlings. 
Preventions and remedies. — The only course that can be recommended is the cultivation 
of rust-resistant varieties of wheats. In other wheat-growing countries, it has been noticed 
that certain varieties of wheat are less susceptible to rust than others, and by selection and 
crossing varieties have been jiroduced which are almost, if not cjuito, immune against the 
disease. This might bo attempted in the Sudan in districts where rust is prevalent, while 
varieties of wheat, known to bo rust resistant in other countries, might also be given a trial. 
Smuts 
Dura is attacked in this country liy several species of smut fungi. 
The smuts belong to the family Ihtilai/inacece and are all parasitic on the higher plants. 
They are especially injurious to cereal crops. 
The following is a rough outline of the life-cycle of one of the cereal smuts. 
The fungus passes the resting period in the form of chlamydospores. These are usually 
sown with the seed and both germinate at about the same time. The chlamydospores give 
rise to conidia, and these infect the young seedling plants, infection taking place in the 
soil. The mycelium of the fungus spreads throughout the tissues of its host-plant, but 
does not produce any malformation until the head begins to form. It then attacks the 
ovaries of the flowers, which become metamorphosed into sacs filled with chlamydospores. 
On the sac rupturing these chlamydospores are blown about by the wind and many adhere 
to healthy grains. If this grain is used for seed in the following season, the chlamydospores 
are enabled to produce conidia and infect the seedlings in the manner described above. 
The life-cycles of the various cereal smuts differ in detail. 
Preventions and remedies. — The best method of dealing with the smut fungi is to 
sterilise the seed before sowing, and thus destroy the chlamydospores before they have had 
a chance to infect the seedling. 
This can be done by soaking the seed in a solution of copper sulphate (1 lb. copper 
sulphate in 20 gallons water) for a period of from twelve to sixteen hours, and then placing 
it in a solution of milk of lime (14 lb. quicklime in 20 gallons water) for five minutes. The 
grain should be spread out to dry before sowing. 
This method has been found to be effective against the smuts of wheat, rye and oats, 
and should prove of value against the dura smuts. 
Dura plants infested by a smut fungus are usually conspicuous by their relatively 
larger size when compared with the surrounding healthy plants. It should be practicable, 
therefore, to collect by hand and burn the diseased heads before the chlamydospores have 
become sufficiently developed to be carried about by the wind. 
II ISCEL LANEOUS 
Aspidoniorpha, sjip. 
Plate XXX., figs. 6, 8 
The two beetles illustrated on Plate XXX, figs. (1 and 8, are members of the interesting 
grou}) Cassidides, sub-family Gri/ptostonies, family I'lirysomelidu'. Aspidomm’piia clilorolica, 
Oliv., was sent from Uganda by Mr. Dawe ; . 1 . mutahilis occurs in the Sudd region. 
Smuts 
Attacking 
cereals 
Life-cycle of a 
smut fungus 
