Maskell. — On New Zealand Desmidieoa. 15 



The form with concave sides approaches to C. aiiccps, Lun- 

 dell, but it is larger, and the ends are not emarginate. I observe 

 that Wolle's figure of C. anceps (" Desm. of U.S.," pi. xviii., 

 fig. 11) differs considerably from Lundeli's. The convex form 

 resembles G. part id um, Brebisson, but is also much larger. 

 The three outlines which I give were taken from a gathering 

 in which the plant occurred rather plentifully. Mr. W. B. 

 Turner informs me that he has seen from India a plant some- 

 thing like mine, and thought of giving to it the name of 

 C. varians. Herr G. Lagerheim tells me that he has had my 

 plant growing in a greenhouse at Berlin for two years : he 

 does not mention the locality whence he procured it, but this 

 could hardly have been New Zealand. 



Cosmarium curtum, var. attenuatmn, Brebisson. Plate II., 

 fig. 16. 



Sufficiently near to the European species, I believe, to 

 permit identification. It will be noticed that this New 

 Zealand form has a slightly elliptical end-view, being narrowed 

 as seen from the side. It is just possible that this may be 

 sufficient to distinguish it from Brebisson's plant, or, at least, 

 to suggest that it should be named "forma compressa." But 

 for the present I prefer leaving it as it is, subject to future 

 revision. In dimensions it is rather smaller than the type. 



Long., 35 /x ; lat., 15 fi ; crass., 10 jx. 



Otaki. 



Cosmarium retusum, Perty ; var. Icevc, Eoy and Bisset. 

 Plate II., fig. 17. 



This plant differs from Perty's type in the total absence of 

 granules. Lundell ("Desm. Suec," p. 36) remarks that the 

 granules of G. retusum are not easily observed ; but they are 

 undoubtedly absent in the New Zealand as in the Japanese 

 form. 



Long., 17-8 /x; lat., 13-5 /x ; crass., 7 /x. 



Hawke's Bay ; Otaki. 



The dimensions given are rather smaller than those of Eoy 

 and Bisset (" Japan Desm.," p. 195), but the plant seems to be 

 otherwise identical. 



Cosmarium pacJnjdermum, Lundell, forma intermedia. 

 Plate II., fig. 18. 



Long., 81 fi; lat., 55 /x ; crass., 19 /x. 



Christchurch ; Hawke's Bay ; Kaitoke ; Otaki. 



This plant seems to be intermediate in size between 

 Lundeli's original type and Nordstedt's "var. minus " (" Norges 

 Desm.," p. 18). The segments are quite round, as in the 

 type; but in side-view they are rather narrower and more 

 attenuated. 



