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Psyche 2:209, 1877.

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PSYCHE.
ORGAN OF THE CAMBRIDGE ENTOMOLOGICAL CLLB EDITED BY GEORGE DIMMOCK AND B. PICKMAN MANN. Vol. 11.1 Cambridge, Mass., February, 1879. [No. 58. On the Repugnatorial Glands in Eleodes.
The repugnatorial glands of Eleodes gigantea and 3. dentipes are situated on both sides of the intestinal tract, imbedded in the fat-bodies. They are two reddish-brown, semi-bilobed pieces, cylindrical at the upper, longer lobe and more flattened at the lower, shorter part, the latter being on the inner side, as the figure shows.
Their extent is from the base of
the la~t up to the middle of the second integumental segment, and they have an average length of 6.5 mm. sess these glands, and on teasing the living specimens Q4
Both E. gigantea and 3. dentipes, male and female, pos- Fig. lo.
in the breeding cage, they stand on their anterior and middle legs, holding the abdomen high up, and spirting the contents of the glands left and right. I have handled several hundred live specimens, and, in every case, the spirting had a sidewise direc- tion. The liquid stains the human skin, and the stains are not easy to remove. In some cases, when the secretion is spirted on a glass slide, it solidifies within a few seconds, forming an orange-colored magma of minute crystals; in other cases it only partially crystallizes, and in others it remains entirely liquid. It is, in all cases, of an acid reaction, and of an in- tensely penetrant odor, causing the eye to laclirymate. It is soluble in water, alcohol and ether.
Boiled with concentrated
sulphuric acid and alcohol an ethereal aromatic vapor is pro- duced, indicating the presence of one or more organic acids. The smell of the glandular secretion is to my knowledge incom- parable with anything else, and very peculiar. Having tested



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for valerianic acid in the usual way with neutralized soda-solu- tion upon sesquicl~loride of iron, no red precipitate of valerian- ate of iron was formed, nor have I obtained a bluish-white opalescent liquid of butyrate of copper on adding acetate of copper. Uric acid was also found to be absent, on treating I with nitric acid and ammonia in the usual way ; neither could I detect formic or acetic acid, nor did boiling with caustic soda libar.ite amm~iiia. A few drops of tlis secretion, put 011 a piece of dry caustic soda, turned at first dark green, became in a few seconds dirty brown, and cleared up to a brownish red after several hours. So far I am not aware of the constituents of the secretion, and, on sending some of it to Prof. Chandler, asking his kind advice, I was told that a payment of sixty to seventy-five dollars, in advance, would be necessary to have an accurate analysis made.
The secretion was gathered gradually, by holding live speci- mens into a test-tube containing 10 grams of dry caustic soda. About 60 drops have accumulated during a period of three months. Carl 3. Gissler.
Attacks of Native Insects upon Imported Trees. It is often stated that foreign trees, and other plants imported into a country, are not attacked by the insects peculiar to the new surroundings. The presumed immunity is even quoted as an advantage in the use of such trees for forest trees. But the immunity is apparently only presumed, at least for plants and trees after their entire acclimatization. When I was a boy I saw extensive plantations of Pinus strobu,s and of Bobinia pseudacacia, which grew excellently and seemed not to be at- tacked by native insects. This was between 182-1: and 1830. Later, things have changed considerably ; nevertheless Ratze- burg contends that at least deciduous trees are attacked less (as lie states it to be a common fact) than pine trees. There- fore exotic oaks near by indigenous ones infested by Clirysomela and Tenthredo are attacked less. The Pinus strobus accord- ing to Noerdlinger, is attacked even more than European pine, being damaged together by Scolytus polygraphus, S. piniperda,



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