Hosts:- Ranunculus depresses T. Kirk. On leaves and petioles. Herb. No. 81. Mount Guinevere (Canterbury), W. D. Reid ! 15 Oct., 1919. Ranunculus geraniifoliis Hook. f. Herb. No. 315. Mount Hector (Wellington), 1,500 m., E. H. Atkinson ! 6 Feb., 1921. Ranunculus insignis Hook. f. Herb. No. 372. Mount Dennan (Wellington), 1,500 m., E. H. Atkinson ! 7 Jan., 1922. Ranunculus Lyalli Hook. f. Herb. No. 81. Waimakariri glaciers, T. Kirk ! Jan., 1883. McKinnon's Pass (Otago), E. H. Atkinson ! 16 Jan. 1920. Sugarloaf, Cass (Canterbury), 650m., W. D. Reid ! N. R. Foy ! 20 Jan., 1922. Punch-bowl Falls, Arthur's Pass (Canterbury), 1,000 m., E. H. Atkinson ! 15 Nov., 1922. Ranunculus nivicola Hook. Herb. No. 496. Mount Egmont (Taranaki), 1,200-1,500 m., W. D. Reid ! N. R. Foy ! 2 Jan., 1922. Ranunculus pachyrrhizus Hook. f. Herb. No. 372. Lake Harris (Otago), 1,100 m., W. D. Reid ! 6 May, 1921. Ranunculus repens L. Herb. No. 81. Weraroa (Wellington), 100 m., E. H. Atkinson ! G. H. C. 3 Oct., 1919. Sandhills, Levin (Wellington), 30 m., E. H. Atkinson ! G. H. C. 14 Oct., 1922.

0. Spermogones amphigenous, crowded in small groups, mixed with the aecidia, immersed, honey-coloured.
I. Aecidia amphigenous and petiolicolous, crowded in scattered groups, which are seated on slightly inflated spots visible on the opposite surface, on leaves the groups are orbicular and up to 5 mmm. diam., on stems they are elliptical and up to 10 mm. long; orange. Peridia cupulate, immersed, and partly erumpent, 0-25 mm. diam., margins 0.5-1 mm. high, erect, slightly expanded, not revolute, brittle, white, finely lacerate. Spores polygonal, elliptical, or subglobose, 20-37 X 18-28 mmm.; epispore hyaline, closely and minutely verruculose, 1 mmm. thick, cell-contents pallid orange, granular.

Distribution: World-wide.

With the exception of Ranunculus repens L. all the hosts are endemic. They are all confined to the mountain-ranges. R. insignis and R. geraniifoliis occurs in both Islands; R. nivicola is confined to the North Island, and R. Lyallii, R. .pachyrrhizus, and R. depressus to the South Island. (Cheeseman, 1906, pp. 9-24.)
The aecidium on R. repens may belong to the cycle of any one of several species - for example, Uromyces Dactylidis Otth, U. Poae Rab., and Puccinia Magnusiana Koern. As its connection with those species mentioned above which occur in New Zealand has not yet been worked out, it is retained here for the present. The forms on the several hosts discussed above do not agree with one another in all particulars, differing slightly in the size of the spores as well as in minor details of the peridia; these differences are so slight, and merge one into the other so closely, that it is not possible to separate any one form as being sufficiently distinct to warrant its being raised to specific or even varietal rank. (A drawing of a spermogone of this species is given in Trans. N.Z. Inst; vol. 54,. p. 620). On Ranunculus Lyallii the spermogones precede the aecidia, and may frequently be found arranged in small groups, quite covering the surfaces of the leaves.

Both fungus and hosts [Dactylis glomerata and Ranunculus repens] are introduced; the disease is rarely severe enough to affect growth of the grass. Cunningham (1931a) stated that he had proved experimentally that aecidiosori in Ranunculus repens in New Zealand belong to the cycle of this species.