Rust Fungi on New Zealand Clematis. By G. T. S. Baylis, Botany Department, University of Otago. [Read by title and abstract before the Otago Branch, April 13, 1954; received by the Editor, April 26, 1954.] Abstract Puccinia, alboclava, n.sp. is microcyclic and known only from seedlings of Clematis indivisa. It differs from P. clavata Syd. in having smaller, thinner-walled, unpigmented teleutospores and in forming lesions that are pale in colour. P. clavata is also microcyclic, and differentiated into physiologic races, a form from C. hexasepala being able to cross to C. indivisa while one on C. foetida could not. The uredospore stage previously attributed to P. clavata is described as Uredo puawhananga n.sp. Pycniospores and aecidiospores of Aecidium otagense Linds. cannot infect Clematis. Species which have been tested unsuccessfully as possible alternate hosts of this fungus are Danthonia cunninghamii, Poa astoni, Uncinia australis, Cross 7 Wheat and I.A.B. *iryecorn. Puccinia alboclava n.sp. Microcyclica et sine spermagoniis. Teleutosori hypophylli, in maculis vix incrassatis usque ad. 1 cm. latis insidentes, nudi, pulvinati, in singulos usque ad. 25 mm. lati sed trans aliquantum maculorum confluentes, isabellini vel mellini. Teleutosporae hyalinae, formibus diversis, 26–54μ longae, 11–18μ latae (medie 41μ × 12μ), episporio levi, plerumque tantum 1μ crasso, interdum apice usque ad 2μ incrassato, pedicello brevi. Habitat. In foliis plantae juvenilis Clematidis indivisae. Holotype. Mt. Maungatua, Otago, New Zealand, 1,300ft., coll. G. T. S. Baylis 9/7/1950, in herbario Plant Diseases Division, Auckland, No. 12685. Paratypes. Mt. Hauhangitahi, Volcanic Plateau, S. D. Baker 1/1954, P.D.D. No. 12894; Steep Hill, Merton, Otago, 800ft., Baylis 11/6/1953, O.U. No. 908; Swampy Spur, Dunedin, 1,500ft., Baylis 6/12/1950, O.U. No. 910; Maungatua, Otago, 1,200–1,500ft., Baylis 31/3/1953, O.U. No. 905. Fig. 1.—Uredospores of Uredo puauhananga (left), teleutospores, epibasidium and germinating basidiospores of Puccinia alboclava (right).