Frond rather large; constriction deep, linear; segments in front-view obscurely three-lobed, the basal lobes widely emarginate with very shallow depressions; end-lobe compressed, ends slightly dilated, round, a little protuberant, with a deep narrow notch. At the base of each segment five granuliferous inflations (three on the face and one at each side); above these four others; at the ends an inflation on each side of the notch; altogether eleven inflations on each segment. The granules are conspicuous, and the cytioderm as punctate. Segments in side-view thick, sub-cylindrical, slightly narrowed near the ends, the inflations giving irregular outlines. In end-view the sub-elliptical grooved ends appear conspicuously on the rounded and inflated basal lobes, the granules being conspicuous. Long., 75–80 μ; lat., 40–44 μ; crass., 26 μ; lat. isthmi, 11.8 μ. Hawke's Bay; Otaki. B. Forma minor, var. simplex, var. nov. Plate I., fig.6. Frond much smaller than the last; otherwise similar in outline. Inflations not constant in number: some plants exhibit eleven on each segment, others only seven, the lowest row having only three, the middle only two; inflations granuliferbus, the granules distinct. Cytioderm smooth, or, at least, the puncta are extremely obscure. Zygospore globose, with subulate spines which have very broad bases and rather long points. Long., 53 μ; lat., 26 μ; diam. zyg. ex spin., 27 μ; long. spin., 11 μ. Rutherford's Swamp, Otaki. E. sinuosum was attached by Ralfs (“Brit. Desm.,” p. 85) to E. circulare, Hassell, but has since been considered as separate. The two forms here given do not, as it seems (unless the hitherto undescribed zygospore of the European plant be found to differ), require to be considered as anything but varieties of the type. Nordstedt reports (“N.Z. Alg.,” p. 33) E. sinuosum from New Zealand without remark. The measurements which he there gives (long., 87 μ; lat., 50 μ) are a good deal larger than those of Ralfs. My var. gemmulosum exactly corresponds with Ralfs's dimensions; the var. simplex is a good deal smaller. The measurements I give are constant in a number of specimens observed. I think that the conspicuous granules in the inflations of both, the divided sub-elliptical end conspicuous in end-view, and the shallowness of the depressions in the edges, may be taken as sufficiently distinctive characters: the variable number of inflations is not important. Wolle (“Desm. of U.S.,” pl. xxvii.) figures E. circulare with much-compressed end-lobe, and with a