Vol 59 Iss. 2

It is 80 years since the birth of the outstanding Soviet geologist, Academician Dmitry Vasilyevich Nalivkin. The whole life and activity of D. V. Nalivkin is connected with the Leningrad Mining Institute.

The appearance of new morphological features is confined to a few few few epochs, which in time coincide with the beginning of regressive stages in the history of the Earth's development. In different lines of evolution of quadrangular corals, the main features of skeletal structure appear in a strictly defined sequence, but at different chronological milestones. Among the four-beam corals are distinguished monochronomorphs, confined only to certain time intervals and therefore of great stratigraphic importance, and polychronomorphs - morphologically similar forms of different age.

A detailed study of the Devonian representatives of the family Cyatho- phylloididaeDybowski allowed us to establish that their assignment to the genera Palaeophyllum Billings and Favisiella Dana is inaccurate. Both genera are characterized by the presence of a thin rim, and the first genus is characterized by branching colonies, and the second by massive...

Optimal conditions for modern colonial six-beam corals of the scleractinids are well studied [Bogdanov, 1963; Carrington, 1964; Ommani, 1963; Ravikovich, 1954]. Their distribution is influenced by depth, temperature, salinity, water movement and oxygen supply, and soil composition. Corals reach their maximum development at depths of 20-40 m.

On the territory of the western slope of the Northern Urals and Pai-Khoy, deposits of the middle Devsha Division are widespread. Their characteristic feature is significant facies variability both in area and time: sediments from continental (?) to marine, relatively deep-water sediments are represented here. For stratigraphy and correlation of the Middle Devonian marine sediments, along with other faunal groups, the remains of four-beam corals, which are widespread in these sediments, are important...

Four-beam corals in the Ore Altai belong to the Tarkhan Formation. Until now, the Tournai quadrilateral corals of this area have remained monographically unstudied. The remains of corals of the Tar-Khan Formation were collected during their layer-by-layer study by V. P. Nekhoroshev in Russia. P. Nehoroshev in 1923-1930.

The genus Lytvophytlum Dobr. belongs to the group of rare, very few and therefore poorly studied corals. So far, only two of its species have been described in the literature - the type genus L. tschernowi (Soshk.)from the Upper Carboniferous and Lower Permian of the Urals [Soshkina et al., 1941] and L. dobrolyubovae Vass.from the boundary layers of the Lower and Middle Carboniferous of Donbass [Vasilyuk, 1960]. In addition, coral finds at the base of the Middle Carboniferous of the Urals, identified by I. I. Gorsky in 1938 as L. tschernowi Var. antiqua Gоr. msc.. were also known. mention of which is contained in the works of I. I. Gorsky [1948] and V. D. Fomichev [1953]. Unfortunately, this form by I. I. Gorsky was not published.

The collection of Devonian and Etrenian platy-fossil mollusks that served as material for the present work (collections of R. A. Arakelyan, Institute of Geological Sciences, Academy of Sciences of the Armenian SSR), unfortunately, does not exhaust the richness and diversity of the fauna of Devonian pele- cypods of Armenia. The poor preservation of the overwhelming majority of forms has complicated the study of their internal structure and, in some cases, the generic diagnosis...

The material for the present article was a collection of bivalves collected by V. D. Voznesensky in 1957. D. Voznesensky in 1956 from the Middle Devonian deposits of the Karaganda region of Central Kazakhstan. The merit of the collection is a large number of specimens and their good preservation.

Diagnosis. “Shell oval in shape, smooth or with concentric jets, with prosogyric apices shifted forward. Along the locking margin the teeth are continuous; in the posterior branch up to 50; in the anterior branch 7-15 larger teeth”...

The present work is the result of the processing of Early and Middle Ordovician bivalves of the family Megalodontidae from the collections of O. N. Nikiforova (1951) and V. I. Dragunov (1957) in the basin of the Chuni River and S. A. Knyazev (1968). A. Knyazev (1968) in the Vilyui River basin.

The present article describes four species of the genus Buxtonia (three of them newly established), originating from the Lower Carboniferous of the Alapaevsky region of the eastern slope of the Urals (collection of L. S. Librovich, supplemented by the author's collections).

The author, as a member of a group of paleontologists of the Uzbek Geological Department, has been studying Silurian sediments of the Southern Tien Shan for a number of years. The ostracod forms described here were collected in the areas where stratotypes of the most important Silurian horizons and formations for the Turkestan-Nurata zone were identified: in the middle reaches of the Isfara River (Turkestan Ridge) and in the area of Mount Merishkor (North Nuratau Ridge). The stratigraphic scheme of the Silurian deposits [Kim, Larin, 1968] is based on long studied groups of fossil animals - stromatopores, corals, brachiopods, graptolites...

For many years, the stratigraphic scheme of the Permian deposits of the Urals has been based on the scheme of D.M. Rauser-Chernousova [1940]. It was developed in accordance with the distribution of individual foraminifera complexes along the section. Many of the horizons identified by D. M. Rauser-Chernousova retained their name and were adopted in the Unified Scheme of Permian sediments of the Urals in 1962, and their sections are considered stratotypic.