130 Transactions. 



was also fairly common. Three other species were collected — Senecio lantus, 

 a much-branched, erect, glabrous herb 25 cm. tall, with lanceolate, fleshy, 

 lobed leaves, and rather dense many-flowered corymbs ; Deyeuxia Forsteri 

 littoralis, a stunted form with small short panicles ; and Parietaria debilis. 



(&.) Mariscus Slopes. — Talus slopes at the foot of sea-chfis, and other 

 steep slopes along the coasts, are usually covered with close-growing tussocks 

 of Mariscus ustulatus, among which other plants occur in gxeater or lesser 

 numbers. Next in importance to Mariscus ustulatus are Carex Forsteri insu- 

 laris, Pteris comans, Hypolepis tenuifolia, Scirpus nodosus, and shrubby forms 

 of Myoporum Icetum. 



Carex Forsteri iyisularis forms small tussocks, i-1 m. high, with crowded, 

 drooping leaves, and many semi-erect slender culms bearing numerous 

 compound spikelets, the upper ones sessile, approximate, the lower on long 

 erect peduncles. Leaves 1 m. long, 1 cm. broad, yellowish-green, cori- 

 aceous, margins and keel scabrid. 



Talus slopes are composed of debris weathered ofi the clilf-face. The 

 soil is thus of a loose moving nature, and, having a large proportion of 

 stones, is not touched by burrowing birds. Other coastal slopes, however, 

 having no cliff above them, and hence with a more stable soil, composed 

 of the weathered surface of volcanic tuffs, are used by burrowing petrels 

 and sh arwaters for breeding-grounds during the summer months. The soil 

 is thus everywhere being turned over for many months of the year, and in 

 this respect resembles the moving soil of the talus slopes. Hence a similar 

 type of vegetation is found in both stations. Mariscus ustulatus, whose 

 large tussocks cannot be easily rooted up by the birds, is the principal plant, 

 and in many places the sole occupier, of these slopes. 



Talus slopes in Denham Bay support a dense covering of vegeta- 

 tion + 1 m. high, composed chiefly of Mariscus 'ustulatus, Ageratutn cony- 

 zoides, Pteris comans, Carex Forsteri insularis, and Sicyos australis. Scirpus 

 nodosus grows in tufts along the base of the slopes just above the reach 

 of the waves. 



The steep slopes of Titi Knob, where not covered by forest, form the 

 breeding-ground of large colonies of black-burrowers {Pufpnus chloro- 

 rhynckus) and short-billed titi {(Estrelata nigripennis). The whole surface 

 not occupied by rock is disturbed every year by these two species of sea- 

 birds. Yet it is densely covered with large tussocks of Mariscus ustulatus, 

 with only here and there, except on rocky gTound and clif?s, a few plants 

 of Hypolepis tenuifolia, Pteris comans, Carex Forsteri insularis, Myoporum 

 IcBtum, and perhaps some others. 



The vegetation of Curtis Island is best described under the present head- 

 ing. The inner slopes and top of the crater-ridge are covered either with 

 Mariscus ustulatus or Mesembryanthemiim australe, the two plants generally 

 keeping separate, and each occupying a large share of the surface. Large 

 numbers of sea-birds breed on the island. Black-burrowers and short- 

 billed titi burrow wherever the soil is loose enough for them to move, while 

 the masked gannet {Sula cyanops) lays on the surface, trampling down the 

 Mesemhryanthemum about its nest. When the birds leave at the end of 

 the breeding season the vegetation profits by the amount of guano mixed 

 with the soil, hence a rank growth covers the ground wherever the birds 

 are able to breed. Not uncommon among the Mariscus tussocks on the 

 crater-ridge were plants of Lepidimn oleraceum jrondosum. This plant 

 occurred in the form of much-branched, rounded bushes, I m. or more 



