. Brachiopod genera of the suborders Orthoidea and Pentameroidea. Orthoidea; Pentameroidea; Paleontology -- Paleozoic. GENERA OF THE SUBORDER ORTHOIDEA 119 Superfamily DALMANELLACEA Schuchert and Cooper 1931 Progressive and terminal Orthoidca, probably de- rived out of the Orthidx, and most easily character- ized by their endopunctate test and a primitively bilobed cardinal process. Embraces the following families: Dalmanellida: Schuchert Wattsellidx Schuchert and Cooper Schuchert and Cooper Mystrophoridx Schuchert and Cooper Rhipidomellidas Schuchert Schuchert and C
. Brachiopod genera of the suborders Orthoidea and Pentameroidea. Orthoidea; Pentameroidea; Paleontology -- Paleozoic. GENERA OF THE SUBORDER ORTHOIDEA 119 Superfamily DALMANELLACEA Schuchert and Cooper 1931 Progressive and terminal Orthoidca, probably de- rived out of the Orthidx, and most easily character- ized by their endopunctate test and a primitively bilobed cardinal process. Embraces the following families: Dalmanellida: Schuchert Wattsellidx Schuchert and Cooper Schuchert and Cooper Mystrophoridx Schuchert and Cooper Rhipidomellidas Schuchert Schuchert and Cooper Schizophoriida- Schuchert Linoporellida: Schuchert and Cooper Tropidoleptidae, n. fam. tion. We shall not be surprised, however, if someone points out that punctation had more than one origin. Punctation once introduced, the superfamily shows shell variations similar to those of the Orthacea, a superfamily that arose in the Cambrian, dominated the Ordovician, and vanished with the Devonian. The Dalmanellacea, on the other hand, arose early in the Middle Ordovician (first ones known in the Chazy), differentiated greatly in the late Silurian and early Devonian, spread over most of the world, constantly throwing off new genera, and yet apparently died out with the Permian. The genetic relations seem to be as shown in Table 9. Table 9 MYSTROPHORIDiE DaLMANELLID/E Proschizophoria. BiLOBITIDiE Bilobites Aulacella Heterorthina ORTHIDiE Discussion.—As is seen in the definition of the Dalmanellacea, we lay the superfamily characteristics in the endopunctate shell and the beginning of a bilobed cardinal process. We further are forced to assume that the punctate shell started in a single species of the Orthacea, but unfortunately do not know in which of the older families this tendency originated, since in none of this superfamily is there any endopunctate species or genus. It is this utter lack of endopuncta- tion among the Orthacea that leads us to our assump- Family DALMANELLID
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