Host: Acaena novae-zelandiae T. Kirk. On leaves. Herb. No. 766. I-III. Seashore, Seatoun (Wellington), E. H. Atkinson ! G. H. C. 27 Jan., 1921. Queenstown (Otago), 400 m., W. D. Reid ! 18 Dec., 1921. (Type.)

0. Spermogones similar to Phr. Acaenae.
I. Caeomata similar to Phr. Acaenae.
III. Teleutosori hypophyllous, sparse, elliptical, up to 3 mm long, pulvinate, pulverulent, the spores becoming agglutinated into compact masses, dull greyish-black, naked, with very many spores in each sorus. Spores 4-8-celled, commonly 6-7, oblong-cylindrical, 65-118 X 18-24 mmm.; apex acuminate, seldom rounded, not or slightly thickened, drawn into a long papilla, continuous with the upper cell-wall, tinted, hyaline at the tip, up to 8 mmm. long, base rounded or slightly attenuate, spore slightly narrowed above and below; not constricted at the septa; wall sepia-coloured, 4-6 mmm. thick, coarsely and densely warted, warts hyaline and more numerous apically; pedicel persistent, continuous with the spore, hyaline below, tinted above, up to 100 mmm. long, 4-6 mmm. thick, not or slightly inflated basally, lower half minutely and densely verruculose, germ-pores 2-4 in each cell, conspicuous.

0. Spermagoniis Phr. Acaenae similibus.
I. Caeomatiis Phr. Acaenae similibus.
III. Soris teleutosporiferis hypophyllis, sparsis, ellipticis ad 3 mm. longis, pulvinatis, primum pulverulentibus, demum in solide catervis conglutinaris, pallidis glauco-nigris, nudis, sporis numerosis in soris. Teleutosporis 4-8-cellulo, communiter 6-7, oblongis-cylindricis, 65-118 X 18-24 mmm.; apice acuminato, raro rotundato, leniter necne. crassato, in papillo apice cellulo episporio continuato, tincto, in summa hyalino, 8 mmm. longo, basi rotundato vel leniter attenuato; ad septa non constrictis; episporio fusco-nigris, 4-6 mmm. crasso, rustice solide verrucoso; pedicello persistente, hyalino apice tincto, ad 100 mmm. longo, 4-6 mmm. crasso, basim leniter necne inflato, verruculoso; foramine germinis ad cellulo 2-4, conspicuo.

The host is endemic and is not uncommon throughout. (Cheeseman, 1906, p. 131.)
This rust is characterized by the large size of the teleutospores, large number of cells, dark and thick wall, and acuminate apex. The pedicels are more slender than in our other species, and are not swollen at the base. The large number of teleutospores in the sorus, and the manner in which they are compacted together, serve to separate this from any other species that may be present on the same plant.

Hab.: In foliis vivis Acaenae novae-zelandiae T. Kirk. Queenstown, Otago, New Zealand. W. D. Reid.

Both rust and host plant [Acaena novaezelandiae] are endemic to New Zealand. It is common throughout the country.