BASTERIA44: 69-70, 1980 in On two preoccupied names Polyplacophora (Mollusca) R.A. van Belle Nijverheidsstraat 22, B-2700 Sint-Niklaas, Belgium of continuation of the While preparing a catalogue fossil Polyplacophora, as a logical already published ”Catalogue of living chitons” (Kaas & Van Belle, 1980), two minor nomenclatorial have attention. problems come to my conradi nov. Chiton 1856, 1847. 1. Chiton nom. pro antiquus Conrad, non Reeve, The used for the first time Conrad in Morton name Chiton antiquus was by (1834: 6), of the United States. in the list of fossil shells of the Lower Tertiary or Eocene period As Chiton Conrad no indication whatsoever is given about that species, antiquus in Morton, is nudum. 1834, definitely a nomen established well-definedChiton Reeve 25, and a from (1847: pi. sp. fig. 169) antiquus known Australia. This recent and common species is now as Callistochiton antiquus (Reeve, 1847). Conrad his a fossil Afterwards, (1856: 266) published a diagnosis for Chiton antiquus, of species from the Eocene of Claiborne, Alabama. Whatever the present generic status Chiton 1856, the name is a ofChiton antiquus Conrad, may be, junior homonym antiquus of author the name Chiton Reeve, 1847, and must be replaced. In honour its I propose conradi. bohemicus De Rochebrune, 1883, 2. Chiton rudelsdorfensis nom. nov. pro Gymnoplax non Chiton bohemicus Barrande, 1867. fossil Barrande (1867: 175, pi. 16 figs. 19-28) namedand figured Chiton bohemicus a from the Silurian of known as Chelodes bohemicus species Bohemia, now (Barrande, 1867). created the bohemicus for the De Rochebrune (1883: 63) name Gymnoplax fossil species from the Middle Miocene of Rudelsdorf, Bohemia, Reuss (1860: 257, pi. 8 figs. had Chiton Chiton olivaceus 1-3) published as siculus Gray (?) [= (Rhyssoplax) Spengler, the Mediterranean 1797, a recent species from Sea]. of the Chiton not the 1821, is a As only genus Gymnoplax Gray, synonym genus and the concerned also Linnaeus, 1758 (A.G. Smith, 1960: 165), as species belongs to 70 BASTERIA, Vol. 44, No. 5-6, 1980 the Chiton the correct name becomes Chiton bohemicus genus s.s. (see Sulc, 1936: 25), This Chiton bohemicus (De Rochebrune, 1883). name, being preoccupied by Barrande, 1867, must be I the name Chiton in reference to the replaced. propose rudelsdorfensis , the first discovered. locality where species was REFERENCES BARRANDE, J., 1867. Systeme Silurien du centre de la Boheme, 3: i-xv, 1-179. Prague & Paris. CONRAD, T.A., 1834. Appendix. In: S.G. MORTON, Synopsis of the organic remains of the Cretaceous of the United States: 1-8. group Philadelphia. 1856. of New Cretaceous and Tertiary Fossils, etc. — Proc. Acad. nat. , Descriptions eighteen Sci. Philad. 8 (1854-1855): 265-268. KAAS, P., & R.A. VAN BELLE, 1980. Catalogue of living chitons (Mollusca: Polyplacophora): pp. 12, 1-144. Rotterdam. of the Chiton. — Iconica 4: 1-27 REEVE, L.A., 1847-1848. Monograph genus Conchologia pis. (1847), pi. 28+5 pis. (1848). London. — k. REUSS, A.E., 1860. Die marinen Tertiarschichten Bohmens und ihre Versteinerungen. Sber. Akad. Wiss. Wien, math.-naturw. Kl. 39(2): 207-285. ROCHEBRUNE, A.T. DE, 1883. Monographic des especes fossiles appartenant a la classe des Poly- plaxiphores. — Annls Sci. geol. 14: 1-74. SMITH, A.G., 1960. Amphineura. In: R.C. MOORE (ed.), Treatise on Invertebrate Paleontology, Mollusca 1:141-/76. of Kansas Kansas. part I, University Press, Lawrence, des SULC, J., 1936. Studie uber die fossilen Chitonen, 1. Die fossilen Chitonen im Neogen Wiener Beckens und der angrenzenden Gebiete. — Annln naturh. Mus. Wien 47:1-31..