Description of Metarhabditis giennensis sp. n. (Nematoda, Rhabditida, Rhabditidae) from decaying wood of a riverbank forest in the southern Iberian Peninsula

A new species of the genus Metarhabditis, M. giennensis sp. n., collected from a riverbank poplar forest in the southern Iberian Peninsula, is described and illustrated, including SEM observations. The new species is characterized by its 1.01–1.16 mm long body in females and 0.77–0.98 in males, cuticle with very fine transverse striation, lip region 9–14 µm broad and consisting of six swollen rounded lips fused in pairs, stoma 14–25 µm long with tubular gymno-promesostegostom, pharynx with slightly swollen metacorpus and slender isthmus, nerve ring, excretory pore and deirids located at isthmus level, female reproductive system didelphic-amphidelphic, vulva equatorial (V = 49–50), female rectum length 1.2–1.7 times the anal body width, female tail conical-elongate with acute tip (123–199 µm, c = 5.8–8.2, c’ = 8.2–11.1), male tail conical (34–56 µm, c = 15.5–25.7, c’ = 2.4–3.5), bursa leptoderan, 32–41 µm long spicules with rounded and ventrally bent manubrium, and 17–20 µm long gubernaculum. An updated list of species of the genus and a key for their identification are also provided. [Zoobank URL: urn:lsid:zoobank.org:act:7EBAC9DB-A148-4A1A-97E5-3B796D0839BF]

THE TECHNOLOGY OF MANUFACTURING GLASS BEADS AT GNEZDOVO, SMOLENSK REGION

Over 12 thousand glass beads have been excavated from medieval burials at Gnezdovo. Most fall in nine technological groups similar to those in a collection from the earthen ramparts of Staraya Ladoga. At Gnezdovo, however, hitherto unknown types were found, such as those represented by isolated specimens formed from lumps of molten glass. A few beads appear to have been made on a mold; those with transverse striation had been welded from several pieces. The latter resemble Greek and Roman era specimens from the Northern Pontic region. For the fi rst time in Old Rus, glass beads with a copper pipe are described. This is a rare technique, also practiced in Central Europe. Numerous specimens from Gnezdovo are two-layered, others are made from a pipe, from a rod, mosaic, or curled. Some experts argued that the use of pipe as a core is motivated by the economy of paste of which beads were made. Pipe cores in cobalt beads might facilitate shaping. Since cobalt-colored beads and bracelets were popular in AD 800–1100, economy cannot provide a universal explanation. The fact that other materials, such as copper and ceramics, were also used is another proof thereof. Generally, such beads are rare not only in Gnezdovo but elsewhere in Kievan Rus as well.

Paravulvus rhodopensis sp. n. (Nematoda: Nygolaimidae) and three known species from Bulgaria, with notes on the taxonomy of the genus

One new and three known species of the genus Paravulvus Heyns, 1968 from forests in Bulgaria are described and illustrated. Paravulvus rhodopensis sp. n. is a bisexual species characterised by a relatively thick cuticle with fine transverse striation, head region offset by a depression, mural tooth deltoid 6-7 μm long, presence of paravulvae posterior to vulva, tail bluntly conical rounded, 24-28 μm long with 7-10 μm hyaline part. Males with one adanal pair and a row of 11-14 supplements, spicules 31-42 μm and tail 22.0-26.5 μm long. Additional morphological and metrical data for P. acuticaudatus (Thorne, 1930), P. hartingii (de Man, 1880) and P. heynsi Vinciguerra, 1987 are presented. Paravulvus acuticaudatus and P. heynsi are new geographical records. An emended diagnosis and revised classification of the genus Paravulvus are proposed, and an identification key to the species is provided. Paravulvus paraamphigonicus (Altherr, 1950) is regarded as a synonym of P.hartingii.

Memoirs: A Simplified View of the Histology of the Striped Muscle-Fibre

The chief results at which I have arrived may be summarised as follows: There is an intracellular network present in the striped muscle-fibre of Dytiscus, the Bee, Prog, Lobster, Crayfish, and Rat, which may be most clearly demonstrated by certain methods of gold staining. The network alone is stained by the reduced gold, and, owing to this differentiation, is plainly visible even with comparatively low powers. This network may be demonstrated, though not so completely, in the living fibre, and in acetic and osmic acid preparations. Crossing the fibre transversely, united to the sarcolemnia, and more or less separating the muscle-fibre into compartments, are network partitions--the transverse networks. Running longitudinally down each compartment, and joining the dots at the intersections of the fibres of the transverse network, are a series of fine rods. The arrangement of this network will be made evident by reference to diagrams 1, 2, 3, and 4. This network consists of an isotropous material, and is more highly refractile than the rest of the muscle substance, which is anisotropous. This network serves to explain the transverse striation and other complicated appearances presented by the muscle-fibre, and brings into harmony many of the conflicting statements of histologists on this subject.