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Abstract
The shoot apices of seedlings of Podocarpus and Prumnopitys form resting buds enclosed in cataphylls, whereas those of Dacrydium and Dacrycarpus are naked. Seedlings of Dacrycarpus differ from those of the other three genera in having a whorl of four lateral branches above the cotyledons. These arise in the axils of a whorl of leaves immediately above the first two leaves which form an opposite pair. In all genera the leaves (except those above the cotyledons) arise in spiral phyllotaxis, and in Dacrydium and Podocarpus they remain disposed spirally at all times, except in young plants of P. hallii in which the leaves may be secondarily arranged in two ranks. Young plants of Dacrycarpus have branches with their leaves disposed in two ranks though initiated spirally. Adult trees of the two species of Prumnopitys have plagiotropic branches with leaves disposed secondarily in two ranks and this occurs from the earliest seedling stages of P. ferruginea. The seedlings of P. taxifolia, however, pass through a stage with the leaves arranged spirally. Prumnopitys is notable, also, for the sympodial habit developed even in the first year seedling of P. ferruginea, and for the divaricating juvenile habit and reduced foliage of young plants of P. taxifolia. The known adult features of these conifers are summarised, and non-New Zealand relatives briefly compared, with emphasis on taxonomic relationships.
