Maskell. — On the Neiv Zealand Destnidiese. 239 



2. Sphserozosma, Corda. 

 8. pirtchrum, Bailey. S. (E. XXXV.) 



Occurs in Hawke's Bay, rarely. I have not seen it. Mr. Archer (in 

 Pritch. Inf., p. 724) includes this plant in the genus Spondylosium, as it has 

 no processes uniting the joints. Babenhorst considers Spondylosium only 

 a sub-genus of Sphcerozosma. 



3. Euastrum, Ehrenberg. 

 E. ansatum, Ehrenberg. S. (E. XIV.) 



Not uncommon. From Hawke's Bay. 



4. Cosmarium, Corda. 



C. ralfsii, var. /3, var. nov. 



Fig. 1. 



Differs from the normal form only in its size, which is very small. 

 Length in front view, 37-5^; breadth, 25^. But these dimensions are 

 quite constant, and the larger form has not been present with it in any 

 gathering which I have observed. Were it not for the slightly triangular 

 segments it might be C. oucumis ; it cannot be G. py'ramidatum, as the frond 

 is smooth. 



C. thwaitesii, Ealfs. (E. XVII.) 



Fig. 2. 



Eare. 



I am doubtful about this plant, as I find no trace whatever of any gela- 

 tinous covering, whether for single fronds or colonies. Ealfs says of it, 

 " puncta very indistinct :" the plant here is smooth. Length, 44 /x. 



G. pusillum, Brebisson. 



Fig. 3. 



This is the smallest plant of the genus known to me. I copy Mr. 

 Archer's description (in Pritch. Inf., p. 731) : " Frond very minute, 

 slightly broader than long, constriction acute, segments angulato-trapezoid, 

 slightly narrowing upwards, smooth, angles rounded, ends slightly concave." 

 I think, however, that the plant here is punctate. The plant is scarcely 

 visible below a power of 200 diameters. Length of frond, 12 /.t ; breadth, 

 15 fi. 



Hitherto described only from France (Brebisson) and Saxony (Baben- 

 horst). 



Not common. I have specimens dividing, but no zygospores. 



G. punctulatum, Brebisson. 



Very similar to a young state of G. margaritiferum : indeed Mr. Archer 

 (in Pritch. Inf., p. 733) unites' the two. Babenhorst is doubtful on the 

 point. 



Common, both in Canterbury and Hawke's Bay. 



