Siberians have given the name "gnus" to the blood-sucking dipterous insects which attack man and domestic animals. During the summer in many regions of Siberia and the Far East, especially in forest and marshy areas, many thousands of winged blood-sucking insects attack man, pierce his skin with their needle-like mouth parts and annoy him with their bites. Even if one insect is driven away, one hundred or one thousand more replace it. At no time during a summer day can man be free of this pest. Domestic and wild animals are also annoyed and attacked by these insects.These dipterans affect human health and animal behavior. Productivity at work sites also suffers due to these insects. The full impact of these pests has not been adequately studied but available data indicate significant reduction in output of labor exposed to annoying blood-sucking mosquitoes. According to the data collected by Maslov and Shamrai (1955), labor productivity of the Eleventh Forestcutting Brigade in the Vyazemsk district of Khabarovsk region averaged 88% in the summer of 1953, when there was no protection from blood-sucking mosquitoes. Productivity rose to 110% in the same brigade when dimethylphthalate was used as a repellent. Similar data are available for the Arkhangelsk region (Kalmykov, 1955) and the Karelian Autonomous Soviet Socialist Republic (Lutta, 1956). 8 partly reduced. Having studied this aspect in some members of the family Culicidae, Marshall, Staley and Staley (1935) presented some interesting data on the comparative measurements of the length of maxillae and mandibles in percentage of the length of the proboscis: according to their data, in Culiseta mosquitoes, the maxillae of males are marked by maximum relative length compared to other Culicinae. The results of a special study of this character in various members of Culisetina are presented in Table 1. The table shows that the mandibular index (ratio of its length to that of proboscis along with labial palps) is greatest in males and most variable in members of the subgenus Culiseta s. str. and in Allotheobaldia longiareolata. This index is noticeably low in members of the subgenus Culicella. The maxillary indices also vary in roughly the same proportion (Table 1).Attention should be paid to the structures of the maxillary palps 11 16 pal segments as in other Culicidae (Ivanova, 1960) but only tactile sensillae (trichogen cells) are present on the terminal segment. Maxillary palps of females are also 5-segmented, but the first two are fairly completely fused, the 3rd and 4th segments normal (4th is the longest), while the 5th is underdeveloped and is found as a small knob or button, often hidden in the pit of the 4th segment. In some species, the 5th segment may even be double in length, as pointed out by Natvig (1948) for Culiseta annulata and as mentioned in our data for C. annulata annulata and sometimes for C. bergrothi and alaskaensis. The length of the palp averages 16-29% of that of the proboscis, with a range from 10 (in C. alaskaensis, C. glaphyroptera an...

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Lattice distortions due the implantation of Fe+ ions in InP semi-insulating crystals have been investigated by means of high-resolution x-ray-diffraction and x-ray standing-wave methods. The effects of both the implantation dose and the annealing time were studied. It is shown that the x-ray standing-wave method provides valuable complementary information on strain and damage in the subsurface layer and permits one to distinguish between different distortion profiles that give practically the same kinematical diffraction curve.

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The Sermenovo Formation in the eastern limb of the Bashkirian Anticlinorium of the South ern Urals yielded the graptolite Monograptus praedeubeli, the chitinozoans Ancyrochitina ancyrea and ?Ancyrochitina sp. and the acritarch Elektoriskos aff. williereae among other less time specific fossils. The investigated section in the Sermenovo quarry is referred to the Homerian Stage of the Upper Wenlock. Zusammenfassung. Die Sermenovo Formation im Ostflugel des Bashkirischen Antiklinoriums im sud lichen Ural lieferte neben fUr die Altersbestimmung weniger wichtigen Formen den Graptolithen Monograptus praedeubeli, die Chitinozoen Ancyrochitina ancyrea und ?Ancyrochitina sp., sowie den Acritarch Elektoriskos aff. williereae. Die untersuchte Abfolge im Sermenovo Steinbruch kann somit in die Homerische Stufe des Oberen Wenlock gestellt werden.