348 Bulletin of Zoological Nomenclature (4) place the specific name caeneus Buckman, 1925, as published in the binoinen Caenisites caeneus on the Official List of Specific Names in Zoology ; (5) place the generic name Euasteroceras Donovan, 1953 (type species, by original designation. Ammonites turneri J. de C. Sowerby, 1824) (gender of generic name : neuter) on the Official Index of Rejected and Invalid Generic Names in Zoology. References Arkell, W. J., antl Donovan, D. T., 1954 : Bull. zool. Nomencl. 6 : 364. Buckman, S. S., 1898 : Quart. Journ. geol. Soc. Lond. 54 : 442-62. 1918 : ibidem, 73 : 257-327, pis. xxvi-xxxi. 1925, Type Ammonites, 5, Part LII. London. Donovan, D. T., 1953 : Proc. geol. Soc. Lond., No. 1503 : xiii-xiv. Oppel, A.. 1856 (-58) : Die Juraformation. Stuttgart. Reynes, P., 1879 : Monographie des Ammonites. Paris and Marseille. Sowerby, J., 1818 : Mineral Conchology 2 : 203, pi. 190. Sowerby, J. de C, 1824 : Mineral Conchology 5 : 75, pi. 452. Spath, L. F., 1923 : Quart. Journ. geol. Soc. Lond. 79 : 66-90. 1946 : Ann. Mag. 7iat. Hist. (11) 12 : 490-496. COMMENT ON THE PROPOSED USE OF THE PLENARY POWERS TO SUPPRESS THE GENERIC NAME "CAENISITES" BUCKMAN (S. S.), 1925 (CLASS CEPHALOPODA, ORDER AMMONOIDEA) By R. V. MELVILLE, M.Sc. {Geological Survey and Museum, Lorulon) (Commission's reference : Z.N.(S.)798) (Communication received 3rd August 1954) 1 have no claim to a specialist knowledge of airmionite-systematics, but from a general acquaintance with the group of ammonites in question, I feel that Dr. Spath's objections to the proposal that Caenisites be suppressed, carry more weight than the arguments put forward by Dr. Arkell and Dr. Donovan. I find it difficult to understand how these specialists can, in view of their reputation for scientific objectivity, question whether Caensites caeneus belongs to the turneri group of ammonite species. The close relationship between C. caeneus and this group seems to me as obvious as any point of a taxonomic nature in fossils can be. The malformation of the holotype does not obscure the features which betray this relationship and upon which the generic assignation is based. At the most it might make sjiecific determination difficult in the case of a specimen showing no overlap with the normal portion of the holotype ; though even this difficulty is diminished if Dr. Spath's view (that C. caeneus is a malfoi-med variant of Ammonites plotti Reynes) is accepted.
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