The males of Dendryphantes czekanowskii PRÓSZYNSKI and Heliophanus baicalensis KULCZYNSKI are described for the first time. Both species have a central and eastern Siberian distribution, and are common in the Magadan area of eastern Siberia, USSR.

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The predatory behavior of Gasteracantha mammosa (Araneae: Araneidae) was investigated. This species did not immobilize its prey by wrapping at all, and always immobilized them by biting. It could capture bees, though they stung it. The spider seemed not to be influenced by the stinging at all, perhaps because of the hard body. But the spider could not capture pentatomids in most cases, apparently because of the stink.
This species did not carry its prey suspended on a silk line at all, and large prey were usually pulled to the hub along a radius. This curious carrying method resembled the carrying method of Theridiosoma epeiroides (Theridiosomatidae).

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Thermal properties of drag lines collected from Nephila clavata, Yaginumia sia and Argiope amoena were studied by differential scanning calorimetry (DSC) and thermogravimetry (TG) at temperatures from 20°C to 600°C. The DSC thermograms obtained for N. clavata showed an endothermic peak at ca. 100°C and exothermic peaks at ca. 300, 340, 500 and 580°C. The former could be ascribed to the desorption of water from the protein constituting drag lines and the latter to decomposition of the protein. Tce spider's silk thread was stable even above 200°C but completely decomposed at ca. 600°C. The thermal properties of drag lines were found to change with season and depended on the sex as well as species of the spider. Such difference in the thermal properties may be ascribed to the differences not only in the physical properties such as the morphology of silks, the molecular weight and density but also in the chemical structure such as the amino acid composition.

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Teratological variation in the segmental structure of the abdomen has been studied in five pseudoscorpion species of the European Neobisiidae, four from the genus Neobisium CHAMBERLIN and one species of the genus Roncus L. KOCH.
A total of 78 abnormal specimens have been found. These were dissected thoroughly and subjected to the pathomorphological analysis. It was found that the frequency of anomalous pseudoscorpions was variable, depending on the collection site, developmental stage and species. The following aberrations of sclerite segmentation have been noted: partial atrophy, hemimery, symphysomery, occurrence of a supernumerary sclerite (?), and different combinations of these anomalies.
Teratological variation of the abdominal sclerites has been confined mostly to adults, with the exception of a single tritonymph. Tergal anomalies have been much more frequent than those affecting sternites. It was also noted that segmental deficiencies occur more frequently in males than in females.
In addition, some generalizations on the relative distribution of segmental anomalies have been made. The possible causes of the origin of these deficiencies in the pseudoscorpions studied have been also briefly discussed.

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