Bulletin of Zoological Nomenclature 349 PROPOSED USE OF THE PLENARY POWERS TO DESIGNATE RHYNCHONELLA REFRACTIFRONS BITTNER, 1890, AS THE TYPE-SPECIES OF THE NOMINAL GENUS NORELLA BITTNER, 1890 (PHYLUM BRACHIOPODA, CLASS ARTICULATA). Z.N.(S.) 1445 By D. V. Ager {Imperial College of Science and Technology, London) The generic name Novella Bittner, 1890 {Ahh. k.-k. geol. Reichsanst. 14 : 315) has been in general use in only one taxonomic sense ever since its first publication. In this usage it denotes a group of Triassic rhynchoneUoid brachiopods of Tinusual form, mth the dorsal (brachial) valve deeply sulcate. In nearly all other brachiopods of this group, the dorsal valve is convexly folded to a greater or less degree, and it is the ventral (pedicle) valve that bears a median sinus. In ontogenetic studies of Jurassic rhynchonelloids, S. S. Buckman (1918, Palaeont. Indica (N.S.) 3(2) : 1-299) claimed that the dorsal valve is sulcate in the early gro-niih-stages of many of these forms, before the normal median dorsal fold is developed, and coined the terms " norella stage " and " noreUi-form " to denote this condition. More recently (1959, J. Paleont. 33 : 330) I have estabhshed a subfamily noeellxnae to contain Norella and five related genera. Under the Rules, however, it appears that the nominal type-species of the genus is a species with a dorsal median fold, similar to the Lower Jurassic genus Homoeorhynchia S. S. Buckman, 1918, and it is the object of this apphca-tion to prevent the confusing transfer of the generic name from one group of species to another that would be caused by the strict apph cation of the Rules. 2. Bittner included several species in his new genus Norella, but he did not designate or indicate any one of them as the type-species. The first species mentioned was " Rhynchonella sellaris Lbe. sp." [op. cit. : 315), but he did not describe or figure tliis species, which seems to have been cited first merelv because it is geologically the oldest. His chief emphasis throughout was on his own species Rhynchonella refractifrons (: 34). However, Hall & Clarke (1894, N.Y. State geol. Surv., 13th Ann. Rep. (1893) : 833) designated " Norella 8ell%ris Laube " as type-species, while still following Bittner 's emphasis and using one of his figures of Norella refractifrons to illustrate the genus. 3. It is clearly necessary before proceeding further to determine what is the nominal species cited by Bittner as Rhynchonella sellaris Laube. In 1866, Laube (Denkschr. k. Akad. Wiss. Wien 25(2) : 18, pi. 12, fig. 8) had described and figured a species of Norella with the name Spirigera sellaris KJipstein : that is, he clearly identified his material with Terebratula sellaris Klipstein, 1845 (Beitr. geol. topogr. Kenntn. ostl. Alpen 1 : 214). In so doing, Laube was guilty of a gross misidentification, for the true Terebratula sellaris KJipstein is a rhynchoneUoid of normal type, with a strong median dorsal fold like that of the Lower Jurassic genus Homoeorhynchia. Bittner showed that he was aware of this error, for he cited (op. cit. : 85) " ? Rhynchonella sellaris Laube spec. (syn. Spirigera sellaris lOipst. spec, bei Laube . . . non Terebratula sellaris Khpst. !) ". Had Bittner himself designated the species Bidl. zool. Nomencl., Vol. 17, pts. 9-11. September 1960.
Proposed use of the Plenary powers to designate Rhynchonella refractifrons Bittner, 1890, as the type-species of the nominal genus Norella Bittner, 1890 (Phylum Brachiopoda, class Articulata) Z.N. (S.) 1445
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