The paper comprises descriptions of a new genus and species of multiramous dichograptid from the Bendigonian (Be 4) and a new species of Tetragraptus from the Lancefieldian (La 2).

The only important fragment of a Pycnodont fish hitherto known from the English Cretaceous Formations, is the portion of head and trunk figured and briefly noticed by Dixon under the name of Gyrodus angustus, Ag. This specimen displays the splenial bones from the oral aspect; some of the vertebral hæmapophyses; and thick scales with a reticulated ornament, covering only the anterior half of the trunk. The ventral ridge-scales also exhibit very conspicuous serrations. The splenial bones are imperfect, but sufficient to show all the essential characters of their oral face; and these elements present the only unique feature in the specimen. It will be observed that, whereas in all Pycnodont splenials hitherto described the dentition reaches the outer border at least in part of its extent, the bone in Gyrodus angustus has a wide toothless outer margin and an attenuated knife-like edge. The two vacuities in this margin shown in Dixon's figure are partly due to accident, partly imaginary, and there is no doubt that the bone forms a continuous whole.

Being present at the reading of the abstract of my friend Prof. Brögger's paper at the last meeting of the British Association, and having listened to certain laudations thereon, I, with several others, went away with the profound conviction that our Scandinavian colleague was about to bring down upon us a mass of evidence bearing on the differentiation of rocks as irresistible and overwhelming as that of his Viking ancestors in times gone by.

The theory proposed of late years by Mr. Mallet to account for volcanic and earthquake phenomena, while having a charm about it from its very simplicity, is one which must nevertheless meet with very decided criticism from geologists.

The British form recognized under this designation appears to have been first recorded and figured from this country by J. de C. Sowerby (16, pl. lvii, fig. 30), who named it Asaphus or Trinucleus (?). He remarks “that no trace of the position of the eyes remains on the cast, which is also the case with the genus Trinucleus, Murchison”. This form was afterwards allocated by Salter to Phacops (Trimerocephalus) lœvis (Münst.) (13, p. 16, pl. i, figs. 5–7; 14, p. 1, pl. ix, figs. 1–5). Phillips had previously named the same species Calymene lœvis, Münst. (8, p. 129, pl. lv, fig. 250), a determination which both Salter (13, p. 16) and M'Coy (6, p. 404) showed to be at fault. This was complicated by the fact that Münster (7, pl. x, fig. 6; 7a, pl. v, fig. 4) had described two different forms under the same specific name, Trinucleus ? lœvis and Calymene lœvis, the latter of which Salter (13, p. 18) correctly adjudged to be a synonym of Phacops granulatus (Münst.) (Calymene auct.) (7a, pl. v, fig. 3). M'Coy had previously noted the identity of C. lœvis, Münst., with Calymene granulata of the same author, but assigned it to his genus Portlockia (6, p. 404).