382 Oeological Society. 



the evidence shows that the original specimens described by Agassiz, 

 as portions of the mandibular rami of Belonostomus cinctus, are really 

 fragments of the presymphysial bone of this species. Some of the 

 relations of Belonostomus and AspidorJiynchus were pointed out. 



2. " On the History and Characters of the Genus Sejjtastrcea, 

 D'Orbigny (1849), and the Identity of its Type Species with that of 

 Ghfphastnea, Duncan (1887)." By George Jennings Hinde, Ph.D., 



r.G.s. 



D'Orbigny founded the genus Septastrcea on the characters of a 

 coral from the Miocene strata of Virginia, which was named S. siib- 

 ramosa, but no specific description was given. In the same year 

 (1849), Edwards & Haime accepted the genus as valid, but placed 

 S. stihramosa as a synonym of Astrmi ramosa, Defrance — an appa- 

 rently recent species of coral which had previously only been informally 

 described by Defrance. They also included in the genus JS. Forbesi, 

 the orioiual specimen of which was from the Miocene of Maryland, 

 and at that time in the collection of the Geological Survey in 

 London. Later on, in 1852, D'Orbigny claimed that S. Forbesi 

 was but a synonym of his S. subramosa. There is good reason for 

 regarding this as correct, but owing to the fact that D'Orbigny's 

 name subramosa was merely nominal and without description, the 

 later name of S. Forbesi, Edwards & Haime, must be allowed to 

 stand for the type of the genus Sejjtastrcea. 



In 1861 de Fromentel, and in 1867 Prof. Duncan included in 

 Septastra'a several species of Jurassic and Liassic corals, which, how- 

 ever, have no generic relationship to the type form of the genus from 

 the Miocene Tertiary. 



In 1887, Prof. Duncan read a paper before the Geological Society 

 in which he adopted Septastra^a Forbesi, E. & H., as the type of a 

 new genus Glyphastrem, thus leaving in Septastrcea those Liassic 

 and Jurassic species placed therein by himself and de Fromentel. 

 As this proceeding is contrary to recognized rules of nomenclature, 

 the genus Gh/phastrcea will have to be abolished. 



In the type form of Septastrcea, now in the British Natural-His- 

 tory Museum, the walls of the corallites, though closely apposed, 

 are quite distinct ; the theca is formed by the extension of the septal 

 laminae ; the walls and septa in the lower portion of the coraUites 

 are very thin, but the upper portion of the corallites are so infilled 

 with compact stereoplasm that the calices are extremely shallow 

 when mature. There is no true columella, only a pseudo-columella, 

 formed by the union and partial involution of the inner septal 

 margins. The increase is exclusively by marginal gemmation ; 

 fission does not occur. In some cases linear perforations between 

 the septa are shown ; these appear to be for the insertion of the 

 mesenterial muscles. 



The septa in Septastrcea consist of a central layer, dark in micro- 



