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the passage of the parasite of the insect. The writer adopted the latter method in the work he is carrying on.
In the appendix, there is a bibliography of 9 works.
87- The Occurrence of the Citrus Red Spider (Tetranychus mytilaspidis Riley) on Stone and Pomaceous Fruit Trees in Oregon.
EWING, H. E. in Journal of Economic Entomology, Vol. 5, No. 5, pp. 414-415. Concord,
In November 1911, while examining some leaves and twigs of apple trees at Corvallis, Oregon, for the common red spider (Tetranychus telarius L.), the writer came across Tetranychus mytilaspidis Riley, the wellknown red spider of citrus trees in Southern California. Since this observation several records have been made of this species in Oregon.
In the paper under review the writer submits notes on its biology and economy under the influences of its new host plants and new climatic conditions, and presents in tabular form the records of the species made in Oregon,
Here in the autumn eggs are deposited on the twigs. These eggs hatch in the following April and the larvae feed upon the tender leaf shoots. These mites continue to feed and reproduce from the time of hatching until the end of the rainy season, but with very little vitality. It is during July that the adults become very active and the eggs are found scattered about all over the leaves, the species becoming very injurious by sapping the juices from the leaves and causing the latter to become pale or spotted and to curl up around the edges.
As means of control summer sprays and, even better, some dormant spray to kill the eggs are advised.
Lime-sulphur is not a satisfactory winter spray for the eggs of this mite. It will not kill the embryos in the eggs at all, but will, however, kill some, and at times perhaps 60 or 70 per cent, of the larvae after they have emerged.
Earias chlorana, a Parasite of Salix viminalis (1).
FEYTAUD, Y. Les Insectes de l'Osier: Earias chlorana Linn. Bulletin de la Société d'Etudes et de Vulgarisation de la Zoologie agricole, Year II, No. 4, pp. 89-97 Bordeaux, 1912.
The osier is one of the most widely cultivated plants of south-west France, especially in the Gironde and Corréze.
Salix viminalis Linn. (“Osier blanc," the basketmakers' osier) is the most common species in the osier beds of this district, and seems to be the most liable to fungus diseases, and to the attacks of parasitic insects. After the month of August, a rust of the genus Melampsora attacks nearly all the leaves.
(1) See No. 876, B. May 1912; No. 1702, B. Dec. 1912.
Amongst the insect enemies of the osier, the goat moth (Cossus ligniperda Fabr.) and Sesia sp., the Longicornia Lamia textor Linn., Oberea oculata Linn. and Aromia moscata Linn., and especially the beetle Cryptorrhynchus lapathi, Linn. make galleries in the underground stems; while the Chrysomelina, of which the writer has already made a careful study (Bulletin de la Société de Zoologie agricole, Bordeaux, 1908 and 1909), Earias chlorana Linn., Sarrothripa revayana S. V., and many other species destroy the portions above grouad.
The two latter species devour the shoots, which leads to the suppression of the terminal buds, and causes the osiers to ramify and to become valueless to the basket maker.
The last-mentioned species is always much rarer than the first in the osier beds of south-west, France. In this district, there are two generations of Earias chlorana annually. The first does havoc in May-June, the second in August-September and passes the winter in the chrysalis condition. The moths, which appear in May and in July, lay their eggs on the extremities of the osier shoots, one on each shoot.
The caterpillar makes a cigar-shaped sheath by rolling together the neighbouring leaves of the terminal bud. It leaves untouched its sheltering sheath, and only devours the inner leaves.
The writer counted more than 50 per cent. of infected shoots in some plantations. No remedial treatment can be practised with the view of affecting the ensheathed caterpillar; the best control method is the collection and destruction of the cigar-shaped sheaths. The use of insecticides or insectifuges is less recommended, since the hatching period of the eggs of a single generation may extend over more than a month, which, together with the rapid renewal of the terminal leaves, would render the application of these remedies very difficult.
To obtain any result, the treatment would have to be repeated every week or ten days during the laying season; this was in fact done by the writer, in his series of experiments. He states that he observed a sensible diminution of the damage after three applications of a simple cupric mixture, and more so when he used a cupro-phenic, or cupro-nicotine mixture. Better results were obtained by dipping the extremities of the shoots into the compound than by spraying them.
These treatments can only be carried ont in the spring, as the osier beds become too thick in August-September.
Cupric mixture sprayings are very efficacious, not only in the case of Earias, but also in that of Chrysomelina, and rusts. It is possible after having once cleared an osier bed of Earias by the repeated removal of the sheathed larvae, to guard against reinfection by the setting of lamps or baited traps.
A bibliography of II publications is appended.
89 Crows and Rooks in Agriculture.
JABLONOWSKY, J (Director of the Budapest Entomological Station) A Varjak a Mezőgaz
This is a detailed study of the part played by crows and rooks in agriculture, according to publications printed in Hungary and elsewhere. The question is one of importance to practical agriculture everywhere where there are large numbers of rooks, and is one which affects the agriculturist, ornithologist and agricultural entomologist. Species of Corvus, especially the rook (Corvus frugilegus L.), have partisans who regard them as actual allies of agriculture, but their detractors aver that they are injurions. The writer belongs to neither side.
In an earlier publication (Kisérletügyi Közlemenyek., Vol. IV, No 2, 1910) and elsewhere, he discussed the data obtained out of Hungary. The present work is a critical study of data collected in Hungary itself, and shows that the supposed utility of the rook was based on false biological views and one-sided statistics. The writer states that the examination of the stomachs of rooks and of other insectivorous birds (killed by thousands) do not furnish the expected proof of their utility, but show, on the contrary, that they have destroyed inoffensive birds. Taking these observations as a basis, M. Jablonowsky concludes that C. frugilegus L. should not be regarded as a wholly useful bird. In places where it builds its nests in large numbers, it is capable of causing considerable damage, which justifies its destruction. In comparison with the harm it does, its utility is very slight. Where it is only a bird of passage, this bird is for the most part inoffensive.
90 Birds and Rats injurious to Rice in the Philippines. See above,
91- The Cat Problem in Australia.
LE SOUEF, A. S. in The Agricultural Gazette of New South Wales, Vol. XXIII, Part 10, pp. 895-896. Sydney, Oct. 1912.
The domestic cat of Australia has become wild and must be included in the list of the destructive animals of that country.
The cats which have become wild, are in some cases animals which have been turned out into the bush by their owners, have run away, or have been liberated by stock owners as enemy of the rabbit.
others a supposed
They have now become established throughout the land and are living on the wild game. They devour small animals, lizards, opossums,
and even lambs, as well as rabbits. In the Macquarie Islands they were very numerous and destructive to the sea-birds, which supply the sealers with eggs. It was therefore necessary to introduce dogs for the suppression of the cats. When the latter were killed off, the dogs then attacked the seals, and therefore had, in their turn, to be destroyed. Where the wild cat has established itself, the ground game and small marsupials have greatly diminished, and it seems that in the future the partial extermination of certain species can be counted upon, while its influence on the rabbit question remains yet to be seen.
Wild cats have practically no enemies in Australia. They seem to be reverting to a specialized type, that of a blotched tabby; in parts of Queensland, they are more or less striped and have a heavy ruff round the neck. In Lord Howe Island, they are very dark, mottled grey, much larger than the average house cat, specimens up to 20 lbs. in weight having been recorded.
ALFREDO RUGGERI, gerente responsabile.