APRIL 4, 1936 NATURE 581 peculia.rity-stenogamy-is known to be a character• by Massee• without success. Ewing and Smith1 istic of the above-mentioned species and also of two recently established mites from strawberry on others, namely, Aedes aegypti and Anopheles maculi• plants of Cyclamen, Delphinium, Saintpaulia and pennis var. atroparvus. Achyranthes. The following observations recently recorded in our The present small experiment is believed to be the laboratory in regard to the mosquito Theobaldia first successful demonstration of the ability of the subochrea, Edwards, appear to be worthy of note. mite to transfer from cyclamen to strawberry. It may be mentioned that, in Great Britain, T. D. 0. BOYD, subochrea is one of the rarer species, having so far University, w. E. H. HODSON. been recorded from eight localities only. These are R eading. Earl's Court (London), Hayling Island (Hants), Hull F eb. 12. (Yorks), Isle of Sheppey (Kent), Letchworth (Herts), 1 Ewing, H. E., and Smith, F. F., "The European Tarsonemid Rustington (Sussex), Southampton (Hants) and Strawberry llflte identical with the American Cyclamen Mite", Proc. Studland (Dorset), Ent. Soc. Wash., 36, No. 8-9, 267-268 (1935). 2 Massee, A. M., "Further observations on the Strawberry Tarsone• On February :t and 15 last, we collected third• mid Mite (TarsExeter, of dried kale or dried alfalfa caused an alleviation of and were found to be heavily infested with Tarso• gizzard erosion. Quantities of these extracts equiva• nemus pallidus, Banks, which was causing injury lent to one fourth per cent of dried substance were typical of that normally associated with infestation adequate in preventing deficiency of the anti• by this mite. A few of these flowers were placed on hremorrhagic vitamin, and were shown by assay to the crown of a strawberry plant, which was kept in be of n early equal potency in this respect. However, the laboratory. By the beginning of January 1936, the quantity of alfalfa extract required to prevent the young leaves of this plant were showing symptoms or cure gizzard erosion was about a hundred times typical of Tarsonemus damage. The plant was the adequate anti-hremorrhagic dosage, while the examined on January 7, and mites were seen to be quantity of kale extract required was about twenty plentiful between the folds of the young leaves. A times the adequate anti-hremorrhagic dosage. It was more critical examination on January 9 resulted in thus shown that the anti-gizzard-erosion activity of the discovery of adult mites inside the crown as well these extracts was not proportional to their anti• as on the young leaves. hremorrhagic activity. Ewing and Smith 1 have recently found that Afterwards, it was found that the non-saponifiable Tarsonemus pallidus, Banks, and T. fragariw, Zimm., fraction of these extracts exerted no appreciable are synonymous. Under the former name, the mite effect on gizzard erosion when fed at levels up to the is a pest of cyclamen, begonia, etc., both on the equivalent of 40 per cent of dried substance, although Continent, in America and in England. Under the these levels provided massive dosages of the anti• latter name it has been regarded as a pest of straw• hremorrhagic vitamin. Tests were then conducted berry only•. This is one of the few outbreaks of T. with both the saponifiable and the non-saponifiable pallidus on cyclamen that has been reported in fractions of kale lipids and it was found that the Great Britain for some years, though the mites anti-gizzard erosion activity was localised in the apparently used to be very common on cyclamen saponifiable fraction. and begonias grown commercially under glass. Other dietary supplements tested for potency in The transference of T. pallidus from strawberry to prevention of gizzard erosion and found negative cyclamen, begonia and raspberry has been attempted were cod liver oil 5 per cent, wheat germ oil 5 per cent,

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