Name Changes in the Orchidaceae Consequent Upon Amendments to the International Rules
[Read before the Auckland Institute, February 20, 1952; received by Editor, March 14, 1952]
The latest amendments to the International Rules of Botanical Nomenclature (Stockholm, 1950) make it necessary to again alter several names only recently published. In Trans. R.S.N.Z., 76, 1947, 574, I stated: “Cockayne (Vegetation of New Zealand, 1928, 7) has been followed also in the treatment of the compound species, and the creation of a varietal name for the erstwhile type form”. This was not then the standard procedure in all branches of taxonomic botany and caused some confusion. The principle has now been confirmed by the amended article 28, which reads: “For nomenclatural purposes, a species and any taxon below the rank of species is regarded as the sum of its lower taxa, if any. The description of a subordinated taxon which does not include the type of the higher taxon automatically creates a second subordinated taxon which includes the type of the higher taxon”. Article 28 goes on to provide for the naming of the type-including taxon: “If a taxon of whatever rank lower than a species, which includes the type of the species, is to be referred to by name, it must be designated by the correct specific epithet of the species, but contrary to article 46, without citation of an author's name”. This last sentence is further supplemented by an amendment to article 68: “Subdivisional epithets as typicus, originarius, genuinus, etc., are illegitimate … and must be rejected”. The names I have given to the type-including forms of compound species must therefore be replaced by a repetition of the specific name as follows:
Pterostylis nutans R. Br. var. nutans
Syn. Pt. nutans R. Br. in Hatch, Trans. R.S.N.Z., 77, 1949, 237.
Pterostylis montana Hh. var. montana
Syn. Pt. montana var. typica Hh. in Trans. R.S.N.Z., 77, 1949, 239.
Pterostylis banksii R. Br. ex A Cunn. var. banksii
Syn. Pt. banksii var. typica Hh. in Trans. R.S.N.Z., 77, 1949, 241.
Thelymitra venosa R. Br. var. venosa
Syn. Th. venosa var. typica Hh. in Trans R.S.N.Z., 79, 1952, 390.
Thelymitra ixioides Sw. var. ixioides
Syn. Th. ixioides var. typica Hh. in Trans. R.S.N.Z., 79, 1952, 393.
Thelymitra longifolia J. R. and G. Forst. var. longifolia
Syn. Th. longifolia var. forsteri (Sw.) Hh. in Trans R.S.N.Z., 79, 1952, 396.
Corybas macranthus (Hook. f.) Reichb. f. var. macranthus
Syn C. macranthus var. typicus Hh. in Trans. R.S.N.Z., 76, 1947, 579.
A problem is presented by Pterostylis trullifolia Hook. f. I have not yet been able to trace the holotype of this species. The original description in Flor. Nov. Zel, 1, 1853, 249, “… periantho basi erecto dein decurvo, sepalis lateralibus apice
filiformibus supremo petalisque acuminatis, labello lineari, appendice apice penicillata…” could be applied to the flowers of half a dozen Pterostylis species and certainly to any one of the three varieties of trullifolia. The labellum-tip and sepalar sinus, the form, size and position of the cauline leaves, and the degree of vein-embossment of the rosette leaves—characters which obviously separate the varieties—are not mentioned by Hooker. I would suggest that the existing varietal names, alobula Hh., gracilis Cheesemn., and rubella (Col.) Hh., should be left as they are unless and until the holotype is discovered and it can be ascertained which variety includes the type form.
I have just discovered the description of Thelymitra pauciflora var. pallida W. H. Nicholls. Orchidologia Zeylanica 2.1934.159 (illustrated in Nicholls. Orch. Austr. 2.1952.t33) which effectively renders Th. pauciflora a compound species and makes the valid name of the New Zealand plant (which is identical with the type) Th. pauciflora R. Br. var. pauciflora.