Oliver. — Veyetation of the Kermadec Islands. 143 



((/.) Phijsiognoymj. — The wet-forest formation covers the top of the 

 crater-ridge from Moumoukai to Expedition Hill, and the ridges rmming 

 south-west from Mount Junction to Bollons Peak, and north-west from 

 Expedition Hill, over Big Hill, towards Hutchison Bluff. The height of 

 this area above sea-level is mostly over 300 m., but wet forest extends 

 below this limit on the southern sides of the ridges and in deep gullies. The 

 remainder of the forest on Sunday Island is of the dry type. There is no 

 sudden change noticed in ascending the hills from sea-level to their summits, 

 as dry forest passes gradually over into wet forest. Between typical wet 

 forest and ordinary dry forest, however, there is a marked difference. In 

 the transition forest a mixture of plants occurs, and Ascarina lanceolata is 

 found in company with Rapanea kermadecensis shaded by tall Metrosideros 

 villosa. 



(1.) Dry forest: Viewed from above, the dry forest presents a sombre 

 appearance, the dark-green foliage sf Metrosideros villosa alone being visible. 

 By about June the monotony is relieved by the appearance of young shoots 

 covered with white tomentum, and later, in October, some trees begin to 

 flower, but not till late in November is the flowering general. Then the 

 forest must be a blaze of red, for the scarlet flowers are produced in great 

 profusion, but by the end of the year they are mostly over, and dull-green 

 foliage again dominates the landscape. 



The general height of the dry forest is about 20 m., and three tiers of 

 vegetation may be distinguished. In places the forest-floor is strewn only 

 with dead leaves and twigs, and there is no undergrowth. Usually, how- 

 ever, an undergrowth is present, varying in its composition in different 

 parts. A dense growth of Pteris conians 2 m. high forms the low^est tier 

 of vegetation in many portions of the island. Intermixed with this fern 

 are Macropiper excelsum major, Polystichum aristatum, Doodia media Milnei, 

 Oplismenus undnlntifnlitis, Adiantum hispidulum, Blechnum capense, Dryo- 

 pteris setigera, and other plants. 



On Low Flat Cenchrus cahjculatus is abundant, and at the base of the 

 cliffs in Denham Bay Hypolepis tenuifolia, with fronds 3-4 m. tall, is 

 plentiful. 



In Denham Bay Nephrolcpis exaltata forms an almost impenetrable mass 

 of vegetation 1-2 m. high, with few other plants intermixed. Polystichum 

 aristatum also forms the undergrowth in various parts of the island, and 

 in Denham Bay Nephrolepis cordifolia claims areas to the exclusion of all 

 other plants, its matted roots spreading over the ground, over fallen logs, 

 and ascending the stems of tree-ferns. 



Seedlings of trees, notably Corynocarpus Icevigata, and the palm Rho- 

 palostylis Baueri, often form thick patches on the forest-flocr. 



In Coral Bay the undergrowth is a more or less dense growth of Macro- 

 piper excelsum major, difficult to get through. Mixed with it is a fair pro- 

 portion of Pteris comans. The Macropiper plants have each several stems, 

 sometimes 5 m. long and 23 cm. in circumference at the base, and arched 

 in a more or less horizontal direction. 



Thus several distinct plant-communities contribute to the undergrowth 

 in the dry forest of Sunday Island. 



The second tier of vegetation is composed of small trees, palms, and 

 tree-ferns growing in the shade of Metrosideros villosa. The trees are usually 

 erect, 6-10 m. tall, branch little, and have lax foliage. They are not clos^ 

 together, and are altogether not so numerous as the stems of the Metrq^ 



