Mr. J. Morris on the genus Siphonotreta. 315 XXXII. — Note on the genus Siphonotreta, with a description of a new Species. By John Morris, F.G.S. [With a Plate.] Among the numerous interesting fossils collected by Mr. John Gray from the Wenlock limestone and shale in the vicinity of Dudley, is one which I feel convinced belongs to Siphonotreta (de Vern.), a genus of Brachiopoda, hitherto considered peculiar to the Silurian formations of Russia. The genus having been ])reviously unnoticed in this country, and presenting some pecu-liarities both as regards the structure of the shell and the mode of attachment, it may not be uninteresting to offer a few gene-ral remarks on the subject; more especially as this genus, and some apparently allied forms, have been lately made the subject of a special notice by Dr. Kutorga of St. Petersburg. In this memoir* Dr. Kutorga has grouped together in one family (the Siphon otretese) four genera, Siphonotreta, Acrotreta, Schizotreta and Aulonotreta, which scarcely present any character in com-mon, and have been in part considered by preceding authors as belonging to different groups or distinct subfamilies of the Brachiopoda. Differing from Dr. Kutorga upon the relative value of the cha-racters of these genera, as well as their arrangement or the grouping of them in one family, and certainly objecting to that pernicious system of coining new generic names without a suffi-ciently valid reason, merely for the sake of introducing a more euphonious terminology, I cannot at the same time but freely acknowledge that palseontologists are indebted to him for his elaborate memoir, containing descriptions of some new and in-teresting forms, illustrated with many beautiful figures of the different species. Of the above-mentioned genera, two have been known for about twenty years. One of them, remarkable for the immense abundance with which it occurs in the Lower Silurian grits of the north of Russia, its broken fragments disseminated in the plane of stratification, giving the rock a micaceous appearance, was first made known (1829) as a peculiar genus by Prof. Eichwaldf under the name of Obolus {Aulonotreta, Kut.) ; about the same period (1830), Pander J gave the name Ungula to this fossil, which L. von Buch§ (1840) considered to be an Orthis. The other * Ueber die Siphonotreteae, von Dr. S. Kutorga, Verhandlungen der Kaiserlichen Mineralogischen Gesellschaft fiir das Jahr 1847, p. 250, St. Petersburg, 1848. t Zoologia specialis, 1829, vol. i. p. 274. X Beitrage zur Geognosie des Russischen Reichs, 1830. § Beitrage zur Bestimmung der Gebirgsfonnationen Russlands, 1840.
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