The muscle systems of Lingula, Discinisca, and Crania have been described in considerable detail and in general with progressive accuracy by numerous workers since the time of Cuvier and Owen, and the best and apparently most recent accounts are to be found in two works by Blochmann (1892, 1900). But I am not aware that there exist any diagrams of these systems readily accessible to the palaeontologist; Fischer and Oehlert (1887) give some figures adapted from Joubin (1886), but these are in some respects inaccurate and Blochmann's work, other than on Crania, has not apparently found its way into palaeontological literature. The purpose of the present note is little more than to provide diagrams of the shell muscles of the above-mentioned living genera, and to attempt certain palaeontological restorations. I have had the opportunity of verifying the structures in spirit Lingula and to some extent in Crania, thanks to the kindness of Dr. C. F. A. Pantin.

Holmes, Kossmat, and Hess have independently pointed out that basic to ultrabasic rocks are characteristic of the axes of geosynclines, whereas acid rocks do not occur at that stage of development. Conversely, acid intrusives enter after the contents of the geosyncline have been folded. A short time ago an exhaustive summary of this subject was given both by Bucher and Rittmann.

While descriptions of new ammonites and of entirely new faunas are constantly being published, and (like progress in other sciences) seem, on the whole, to be rather welcomed, some palaeontologists are beginning to deplore the “smothering” of our science “by the abundance of its own material”. I do not agree that systematic palaeontology is in the chaotic state depicted by these authors; in any case, the description of new ammonites will continue. But the question of how authors deal with their “species” is rather different. It has been suggested that older authors, like Quenstedt, still had a very clear conception as to what constituted a “Formenkreis”, but that their successors have lost this sense. Yet as regards atomization of species I do not think that many of the younger palaeontologists will emulate the veteran A. v. Koenen's notorious example of splitting up into innumerable “species” what is virtually a single form of Platyknticeras. By way of contrast, Ilovaïsky, also at an advanced age, established an extraordinarily large number of varieties in a single species of Pavlovia, but his procedure similarly has not been repeated.

Plates VII and VIII show four photographs of U-shaped markings in fallen blocks on the foreshore at Kedcliff, between Redcliff Point and Bowleaze Cove, near Weymouth. They were first noticed by members of the Sedgwick Club during an excursion in March, 1939, and further examination has revealed abundant markings which show interesting features worth putting on record. They do not seem to have been previously recorded from the Corallian Beds, perhaps owing to the abundance of “fucoid” and other strange markings in all the sandstones and oolites of the formation. The examples here illustrated occur in the hard doggers of finegrained calcareous sandstone in the Bencliff Grit, and some occur also on the same horizon between Bran Point and Osmingtoh Mills, two miles to the east.

Watson (1937) in his important work on Acanthodians demonstrated that the mode of jaw-suspension of this group and probably also that of the Arthrodira.Macropetalichthyida, Rhenanida, and Antiarchi was in a more primitive condition than in other Gnathostomes. The hyomandibula of these fishes played no important part in the suspension of the jaws, and the hyoidean gill-slit persisted as such, not being reduced to a spiracle. Watson introduced the name Aphetohyoidea (free hyoid) for the group containing all these fishes, distinguishing them from the more advanced Chondrichthyes and Osteichthyes.