430 PLANTS OF NEW ZEALAND 



have been developed, probably, as a protection against drought 

 and excessive radiation (v. Haastia pulvinaris, p. 424). In 

 other parts of the world, patch-plants are found chiefly in 

 alpine districts. Their occurrence in low-land regions, as in 

 Nevv' Zealand river-beds, is exceptional. In the Swiss Alps 

 they are represented by certain species of Androiucc and 

 Saxifraga, which, however, are rather rosette-plants, than true 

 cushion-plants. They are most abundant in the Andes, where, 

 according to Schimper, their representatives are forms of most 

 diverse aftimty. This really shows that the common habit of 

 the various cushion-plants is due to environment, and not 

 to relationship. Indeed, the conditions of life in some parts of 

 the Andes, are so similar to those in the Southern Alps, that 

 the vegetation in these widely separated districts is externally 

 much alike. A New Zealander, suddenly put down in the 

 Andes of Peru or Bolivia, might still think himself at liome, on 

 account of tlie similarity of the plant forms about hiin, to those 

 of his native land. This resemblance, however, is only in 

 small part due to actual affinity, and much more to parallelism 

 of evolution, resulting from similarity of surroundings. 



The New Zealand Baoidias are often very beautiful, owing 

 to their symmetrj' of form and leaf arrangement. Some are 

 coralloid in appearance, though resilient to the tread, like a 

 good carpet. They grow where other forms of life cannot find 

 a footing, and thus have generally plenty of room to develop 

 their owni individuality. 



Genus Heliclirysii m . 



I[erl)s or simill shrulis. Leaves alternate, woolly. Heads solitary or in 

 corym1:)S. Bracts of the involucre often appearing like petals. Disk-florets 

 4-.5-toothod. Ray-florets few. Pappus-hairs simple, or studded with short 

 hristlcs. About 16 species in New Zealand, all endemic. (Name from the 

 Greek, signifying an eivrln^itinri Jloirei') IG sp. 



Helichpysum selago (The Sclago-like Everlastiwj). 



A shruh, 4 ft. -9 ft. in height. Leaves closely imbricate, leathery, concave, 

 wriolly. Head terminal, sessile, solitar\', not sunk amongst the leaves. Florets 



