24 Transactions. — Bo ta ny. 



fonns of S. scbaldi, Eeinsch, and S. 2^i'ohoscidcum, Brebissou, 

 The large, simple spines, and the straight or concave ends^ 

 seem to separate it from either ; and the spines are not suffi- 

 ciently long nor the segments slender enough for S. aciilea- 

 tum. The two forms reported from New Zealand by Pro- 

 fessor Nordstedt — S. sehaldi, (3 ornaUivi, var. novizelandica ; 

 and *S'. ]}scndoschaldi, var. tonsmu — differ from it in several 

 particulars, both being much more slender, and the last not 

 having a triangular end-view. The large size, the depressed 

 ends, and the conspicuous spines on the edge in end-view dis- 

 tinguish it from the last species. 



Staurastnim vHcaUim, Delponte, var. iniiatnvi, var. \\o\. 

 Plate IV., fig. 42: 



Frond moderate ; constriction shallow and wide. Seg- 

 ments in front-view sub-trapezoidal, widest outwardly ; sides 

 and ends slightly convex ; outer angles terminated by two 

 rather thick spines ; cytioderm smooth or very obscurely punc- 

 tate in the middle, and bearing five or six transverse rows of 

 granules towards the angles ; edges obscurely irregular. End- 

 view triangular ; sides very slightl}' concave, angles slightly 

 inflated and terminating in spines ; granules in transverse 

 rows near the angles only ; edges smooth except by the rows, 

 of granules. 



Long., 45 /x; lat., 60 /x. 



Otaki. 



This plant appears to differ from Delponte's species ("Desm. 

 Subalpin.," p. 167) in the more convex form both in front- and 

 side-views. 



Staurastrum 'pseudoligacantlium, sp. nov. Plate V., fig. 43. 



Frond moderate ; constriction deep, linear ; segments in 

 front-view sub-quadrate, but produced at the sides to sub- 

 acute angles so as to have an irregularly pentagonal form ; 

 sides sinuous, ends straight ; cytioderm smooth in the median 

 space, and bearing tovv'ards the angles a few transverse rows of 

 minute puncta ; edges obscurel}- irregular or crenulate, and 

 bearing between the lateral angles and the straight ends four 

 or five spines, of which two at each side are conspicuous ; the 

 spines of the third angle are visible on the face of the frond. 

 End-view triangular ; sides straight, edges obscurely irregiilar ;. 

 on each side are two spines dividing it in three equal divisions ; 

 cytioderm bearing transverse rows of puncta towards the angles, 

 and three pairs of granules corresponding to the six marginal 

 spines. 



Long., 35-9 yx; lat., 37-9 /x. 



Otaki. 



The figure of S. oligacanthum, Breb., given by Nordstedt 

 (" Desm. Arctose," pi. vi.), differs from the above in a few 



