Plate 165.— MUEHLENBECKIA AXILLARIS. 



Family POLYGONACE Jl. | [Genus MUEHLENBECKIA, Metssn. 



Muehle^beckia^axillaris, Walp. Ann. i, 552 ; Hook. /. Handh. N.Z. Fl. 230 ; Cheesem. Man. 

 Polygonum axillare, Hook. f. in Hook. Lond. Journ. Bot. vi (1817), 278. 

 Muehlenheckia axillaris was originally discovered by Mr. Colenso in the 

 Wairarapa district in 1846, and in the following year was described bv Sir J D 

 Hooker in the London Journal of Botany under the name of Polyqnnum axiUare. 

 It was soon found to have a wide distribution in the mountain districts of both 

 Islands, from the East Cape and Taupo southwards to Foveaux Strait, but so far 

 has not been recorded from Stewart Island. It descends to sea-level or nearlv so 

 in several parts of the Dominion, but is most abundant between 1 000 ft "and 

 3,000 ft. elevation. It is one of the plants nearly always seen in the open river- 

 valleys of the interior of the South Island, or at the base of the shingle-slopes which 

 so commonly cover broad stretches of the steep mountain-sides. But its habitats 

 are really of a varied character. For instance, on the central volcanic plateau of 

 the North Island it occurs plentifully in the shingly or grassy vallevs which radiate 

 from longariro or Ruapehu, on the lower slopes of the mountains, in profusion 

 on the sandy waste to the east of Ruapehu known as the Onetapu Desert, and in 

 not a few localities on the pumice soils of the open Taupo plains. 



Muehlenheckia axillaris varies greatly in size and to some extent in mode of 

 growth. The primary stems creep just under the surface of the ground, or amona 

 loose stones, putting up numerous branches which usually form a dense matted 

 carpet seldom rising much above the ground. The patches may vary from 2 in. 

 or 3 in. to 12 in. or 18 in. in diameter, or even' more, and, although generallv 

 dense, are sometimes lax and open. The leaves vary in size from -^^^ in. to i in. 

 in length, but in shape are tolerably constant. The flowers are'solitarv and 

 axillary, or 2 to 3 together. Like all the New Zealand species, the fruit is 

 usually enclosed in the enlarged white and succulent perianth, but it is quite 

 common to find specimens in which the perianth is practically dry and unaltered 

 in fruit. 



The nearest ally of M. axillaris is undoubtedly M. complexa : but it can easily 

 be distinguished from all the forms of that variable plant by the much smaller size, 

 much more depressed habit, smaller and more uniform leaves, and by the flowers 

 being either solitary or few together. ^ 



Plate 165. Muehlenheckia axillaris, drawn from specimens collected m the Hooker Vallev 

 Mount Cook district, at an elevation of 2,500 ft. Fig. 1, branchlet bearing an e.-^pauded male flower 

 and a young bud (x 5) ; 2, male perianth laid open ( x 8) ; 3, branclilet, with femile flowers ( x ;j) • 

 i, section of female perianth ( x 8) ; 5, nut enclosed in the enlarged and succulent perianth ( x 3) • 

 6, lougituduial section of nut (x 5) ; 7, transverse section of nut (x 5) ; 8, embryo (x 8). 



