Vol 59 Iss. 2

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

The appearance of new morphological features is confined to a few sparse epochs, which in time coincide with the beginning of regressive stages in the history of the Earth's development. In different evolutionary lineages of rugose corals, the main skeletal features arise in a strictly defined sequence, but at different chronological boundaries. Among rugose corals, one distinguishes monochronomorphs, which are confined to specific time intervals and therefore have great stratigraphic significance, and polychronomorphs — morphologically similar forms of different ages.

A detailed study of the Devonian representatives of the family Cyathophylloididae Dybowski has established that their assignment to the genera Palaeophyllum Billings and Favisiella Dana is incorrect. Both of the mentioned genera are characterized by the presence of a thin rim; the first genus is characterized by branched colonies, while the second of the mentioned by massive colonies. ...

Optimal conditions for modern colonial hexacorals of the order Scleractinia are well studied [Bogdanov, 1963; Kerrington, 1964; Ommany, 1963; Ravikovich, 1954]. Their distribution is influenced by depth, temperature, salinity, water movement and oxygen supply, as well as bottom composition. Corals reach their maximum development at depths of 20–40 m.

On the territory of the western slope of the Northern Urals and Pay‑Khoy, deposits of the Middle Devonian are widespread. A characteristic feature of them is significant facies variability both areally and temporally: here sediments range from continental (?) to marine, including relatively deep‑water facies. For stratigraphy and correlation of the Middle Devonian marine sediments, along with other faunal groups, the remains of rugose corals, which are widespread in these deposits, are important. ...

The oldest Carboniferous deposits containing skeletal remains of rugose corals in the Rudny Altai belong to the Tarkhan Formation. Until now, the Tournaisian rugose corals of this region had remained unstudied monographically. Remains of corals from the Tarkhan Formation were collected during their bed-by-bed study by V. P. Nekhoroshev in 1923–1930.

The genus Lytvophyllum 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 species L. tschernowi (Soshk.) from the Upper Carboniferous and Lower Permian of the Urals [Soshkina et al., 1941] and L. dobrolyubovae Vass. from the boundary beds of the Lower and Middle Carboniferous of the Donbass [Vasilyuk, 1960]. In addition, coral finds from the base of the Middle Carboniferous of the Urals, identified by I. I. Gorsky in 1938 as L. tschernowi var. antiqua Gor. 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 was not published by I. I. Gorsky.

The collection of Devonian and Etrenian lamellibranch mollusks that served as the material for the present work (collected by R. A. Arakelyan, Institute of Geological Sciences, Academy of Sciences of the Armenian SSR), unfortunately, by no means exhausts the wealth and diversity of the Devonian pelecypod fauna of Armenia. The poor preservation of the overwhelming majority of the forms has complicated the study of their internal morphology and, in some cases, generic identification. ...

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

Diagnosis. "Shell oval in shape, smooth or with concentric striae, with prosogyral beaks shifted forward. Along the hinge 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 study of Early and Middle Ordovician bivalves of the family Megalodontidae from the collections of O. N. Nikiforova (1951) and V. I. Dragunov (1957) from the Chuna River basin and of S. A. Knyazev (1968) from 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 district of the eastern slope of the Urals (collection of L. S. Librovich, supplemented by collections of the author).

For a number of years, the author, as part of a group of paleontologists of the Uzbek Geological Administration, studied the Silurian deposits of the Southern Tien Shan. The ostracod species described here were collected in areas where the stratotypes of the most important Silurian horizons and formations for the Turkestan-Nuratai Zone have been identified: in the middle reaches of the Isfara River (Turkestan Range) and in the vicinity of Mount Merishkor (Northern Nuratai Range). The stratigraphic scheme of the Silurian deposits [Kim, Larin, 1968] is based on long-studied groups of fossil animals — stromatoporoids, 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 assemblages along the section. Many of the horizons identified by D. M. Rauser Chernousova have retained their names and have been adopted in the Unified Scheme of Permian deposits of the Urals of 1962, and their sections are considered stratotypic.