Page:Transactions NZ Institute Volume 15.djvu/324

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C. gemmiferum, Brébisson. S.

Fig. 4.

A large, handsome species, of the general appearance of C. margaritiferum, covered with conspicuous pearly granules, but differing by having on each segment, at the middle, on both surfaces, a rounded protuberance bordered with granules, which is best seen in end view. (Pritch. Inf., p. 733.)

The typical plant has slightly truncate ends; in our species the truncation is sometimes not apparent.

Seemingly not uncommon in Hawke's Bay. The European species has only been found, I think, in France.

C. obsoletum, Hantzsch, var. punctatum, var. nov. S.

Fig. 6.

Frond in front view almost circular, the breadth perhaps a little more than the length. Edge smooth. Constriction deep, narrow, linear. Segments broader than long, with a minute, bluntly-triangular process on each at the entrance of the constriction on each side; processes convergent, pointing slightly outwards. End view elliptic, showing the processes. Surface of frond distinctly punctate. Diameter in front view, 60–65 μ. Zygospore unknown.

Not uncommon in gatherings from Hawke's Bay.

Professor O. Nordstedt, in a paper which he has kindly sent me on some Algæ in the museum of Lund, figures a species from Java—C. obsoletum, Hantzsch, closely resembling the above. The same plant is found in Rabenhorst (Flor. Alg., sect. iii, p. 227) as Arthrodesmus obsoletus, a variety of A. convergens. Neither author, however, gives more than the very briefest description. But Prof. Nordstedt's figure clearly shows his plant quite smooth, without puncta. In other respects I see no difference, and I think the puncta are not sufficient to raise our plant above the position of a variety.

C. speciosum, Nordstedt, var. inflatum, var. nov.

Fig. 6.

Frond in front view elliptical, the ends not at all or very slightly compressed; segments longer than broad, sides convex; constriction deep, narrow, linear. Segments when empty showing rows of minute semi-orbicular granules, the rows apparently radiating from the centre of each segment, but not reaching quite to it, so that the median space would be smooth if it were not for a number of longitudinal rows of smaller granules, which rows, being slightly curved and not all in focus at once, testify to the presence of a central inflation. The result of the two sets of granules is to

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