Cockayne. — Botanical Exmirsion to Southern Islands. 293 



long X 1-9 mm. broad. This combination of Pea foliosa, 

 Aspidium vestitum, Coprosvia ciliata, Urtica australis, and 

 Stilbocarpa polar is appears to form a distinct association, its 

 presence depending upon the greater amount of shelter that 

 ic receives. This protection from wind is also much increased 

 for its internal members when such an association becomes 

 established, the tussocks themselves affording much shelter. 

 Eight on the summit and most exposed part of a ridge, seated 

 on the ground under the lee of a tussock, the storm could be 

 heard raging overhead, but where I sat was quite calm. 



Where the hillside is less sheltered the vegetation consists 

 of the common meadow-tussock, Aspidium vestitum, and Pteris 

 incisa, with the ever-present Ac(2na climbing m thick masses 

 over the grass and fern. Here both fern and tussock, although 

 still of considerable size, are of much smaller dimensions than 

 in the association described above, and this part of the sub- 

 formation is but a continuation of the fiat meadow. 



The bare ground manured by the giant petrel (Ossifraga 

 gigantea) is occupied by another association of which the 

 endemic Senecio antipoda is the dominant plant. Growing in 

 its company are very thick masses of Accsna, which is fre- 

 quently mixed with Pteris incisa. SteUccria decipiens angus- 

 tata is also common. Senecio antipoda much more resembles 

 the common European groundsel in outward appearance than 

 do any others of the herbaceous section of this genus in New 

 Zealand. It is a very curious fact that, both here and in 

 Chatham Island (23, p. 268), in situations frequented by cer- 

 tain sea-birds there should be an endemic species peculiar to 

 such stations. So far as Gotula featherstonii of Chatham 

 Island is concerned, its growing in ground near the holes of 

 mutton-birds is recognised by the settlers who live in its vi- 

 cinity, and from them it has received the name of the " mut- 

 ton-bird plant." I do not see why rich heavily manured soil 

 should not be just as much a factor in determining the life- 

 form of a plant as illumination, moisture in the air, wind, or 

 any other ecological factor, and to find two plants each of 

 distinctly luxuriant growth growing under very similar con- 

 ditions is suggestive, to say the least. 



Senecio antipoda is a stout herbaceous plant of upright 

 growth. It has a rather thick main stem, hollow m old 

 plants, which gives off numerous lateral branches from its 

 upper portion, and these are furnished above with many 

 usually large, spreading, membranous, green leaves. These 

 when fully grown are broadly spathulate in outline, the upper 

 and expanded half of the leaf being deeply pinnatifid, while 

 the segments are again deeply cut, especially on their lower 

 margin. Such expanded portions of the leaves measure 

 9 5cm. X 77 cm. The lower half of the leaf is entire or 



