6 Transactions. — Bota ny. 



the species to which I first referred it. Nordstedt's specimens, 

 most of which seem to have come from the Canterbury Dis- 

 trict, as mine did, had not the deep incrassation at the ends 

 shown in my pi. xii., fig. 30 (1880). I have re-examined my 

 specimens, and find the incrassation very distinct in most of 

 them, though some are without it. 



Gosmarium crenatum (vol. xiii.). This is C. naegelianumf 

 Brebisson, var. latum of my present paper. 



G. undulatum (vol. xiii.) is C. speciosuvi, Lundell. Vide 

 post. 



G. undulatum, var. /5 (vol. xv.), appears to me now to be 

 somewhat near G. imprcssulum, Elfving, as figured by Eoy 

 and Bisset ("Ja|)an Desni.") ; but I have not specimens at 

 hand for comparison. 



G. inargaritiferum (vol. xiii.). The three forms figured by 

 me in 1880 appear to belong to different species. Fig. 27 is 

 probably G. suhlatum, Nordst. ; fig. 28, G. quaternarimn, 

 Nordst. ; and fig. 29, G. oxniforme, Archer, which is at least 

 very closely allied to G. margaritifcrum. 



G. broomeii (vol. xiii.). This is C. suhlatum, Nordst. ; but 

 I am not able to see the difference between this new species 

 and Lundell's G. latum. 



G. thwaitcsii (?) (vol. xv.) is Penium cucurhitinum , var. siih- 

 polymorplnmi , Nordst. 



G. gcminiferum (vol. xv.) is G. magnificuvi, sp. nov.,- 

 Nordst. 



G. speciosum, var. injiatiim (vol. xv.). Professor Nordstedt 

 makes this G. suhspeciosum, var. validius, var. nov. In accept- 

 ing the correction, I cannot help remarking that the differences 

 between G. speciosum and G. suhspeciosum do not appear to be 

 very important. 



G. cyclicuvi, var. ainpiliatwn (vol. x^•.). In accordance with 

 a suggestion from Professor Nordstedt, I describe and figure 

 this in the present paper as G. subcyclicum, sp. nov. 



C. tetraoplithahnum jB minus (vol. xv.) is C. suhpi^mctu- 

 latum, Nordst. 



Staurastrum avicula (vol. xiii.) is S. suhdenticulatumr 

 Nordst. 



Staur. (Didymocladon) stclla (vols. xiii. and xv.) are forms of 

 S. sexangzdare, Bulnheim. 



Staur. aculeatum (vol. xv.) is S. splendidum of the present 

 j)aper. 



Staur. clepsydra (vol. xv.). This name having been pre- 

 viously taken. Professor Nordstedt, at my suggestion, altered 

 it to S. spenccriamim. He considers the plant a variety of S, 



