Myšlenka založit společnou Evropskou observatoř vznikla patrně na jaře roku 1953 během pobytu amerického astronoma německého původu Waltera Baadeho na observatoři v Leidenu, kde pobýval na základě pozvání Jana H. Oorta (Blaauw, 1991). Rozhovory Baadeho s Oortem vyústily dne 21. června 1953, den před konferencí o galaktické astronomii poblíž Groningenu, v širší diskusi. Té se zúčastnili W. Baade, A. Blaauw, P. Bourgeois, A.-L. Danjon, O. Heckmann, B. Lindblad, J. H. Oort a P. Oosterhoff. Také byl přítomen tehdejší ředitel Holandského národního vědeckého fondu a předseda výboru evropské organizace pro atomový výzkum CERN J. H. Bannier. Tato schůzka, která byla velmi ovlivněna názory W. Baadeho, vedla k založení Evropské jižní observatoře (ESO) v roce 1962., Jan Palouš., and Obsahuje bibliografii
Flat disk models for galaxies are studied on the basis of osscillations of distributed mass around equilibrium configuration. Convincing perspectives to existing galaxy types are available. Several kinds of galactic orbits are possible with peculiar rotation curves. Supersonic and very high velocities seem likely in the central region. Conventional rotation curve breaks into two, inner to the Solar circle and spiral arms. A new model for our galaxy is proposed.
Hypoechinorhynchus robustus sp. n. is described from Notolabrus parilus (Richardson) (Labridae) from Pt Peron, Western Australia. It has a proboscis with 30 hooks arranged in ten longitudinal rows: 5 rows of a small apical spine, a large anterior hook and a small posterior spine, 5 rows of a large anterior hook, a middle spine and a posterior spine. The new species is distinguished from other species of the genus by having a set of 5 small apical spines anterior to the large hooks on the proboscis, by having lemnisci that barely exlend beyond the proboscis receptacle and testes which are more adjacent than tandem. II. robustus also has robust trunk spines anteriorly. Re-examination of Hypoechinorhynchus alaeopis Yamaguti, 1939 (type species) revealed trunk spines that had been overlooked previously. The Hypoechinorhynchidae is made a junior synonym of Arhythmacanthidae because there is considerable overlap between the two family diagnoses, particularly in that both families have a proboscis armature that changes abruptly from small basal spines to large apical (or subapical if present) hooks. The genus Hypoechinorhynchus is placed in the subfamily Arhythmacanthinae because it has trunk spines and a spherical proboscis with few hooks (relative to other arhythmacanthid genera). It is also proposed that Ileterosentis magellanicus (Szidat, 1950) be returned to the genus Hypoechinorhynchus since it was transferred to Heterosentis primarily because it had trunk spines. The other hypoechinorhynchid genus contained only Bolborhynchoides exiguus (Achmerov el Dombrowskaja-Achmcrova, 1941) Achmerov, 1959 and is relegated to incertae sedis.