198 SOME NEW OR LESS KNOWN DESMIDS FOUND IN N. S. WALES, 



Forma trilohata : Forma immatura No.2. (T.v. f.26). 



Nonne Cos. trilohulatam, Reinsch (1). 



Long. 27, 24,27; lat. 16, 17, 18; crass.—, 9, — ;ti. 



Collector. 



Forma incognita is certainly a 3'oung form of f. trilobata, as a 

 semicell of each was found forming one frond. Also an inter- 

 mediate form was noted between f. trilobata and C. indiiratuni 

 t3'^picuin. Nordstedt's fig. of C. irilohiilatum l3 hasichondnim 

 looks, it seems to me, a good deal more like this species than 

 that of Reinsch. Cf. Nordstedt, I.e. T.6, f. 1 1; and Reinsch, Spec. 

 Gen. T.3, f.A2. May not f. trilobata be the same as Cos. frilo- 

 hulafum Reinsch (?). Lundell says, in Desm. Suec. p. 42, 

 **Membrana in centro semicellulae paullura incrassata"; and the 

 size is about the same. 



Cos. suBSPECiosuM Nord., Desm. Arctoae T.6, f.l3. 



Long. 48; lat. 34; crass, 22/li. 



Coogee; rarissime. 



The few specimens seen were, as to shape and size, exactly like 

 the type, save that there were incrassate ridges connecting the 

 granules of the tumour. In one with eiidochrome the pyrenoid 

 was single, I fancied, but it was somewhat doubtful. 



Cos. SUBSPECIOSUM ^ VALiDius Nord., Fr. Alg. N. Z. T.5, f. 10. 



Long 60, 62, 63, 70, 72, 72, 75, 76, 85; lat. 53, 49, 48, 48, 50, 55, 

 50, 59, 56; crass. — , — , — , — , 26, — , — , — , — ju. 



Collector, Moura, Centennial Park, Coogee. 



Nuclei amylacei certissime bini. 



In no specimen have I ever seen nine vertical rows of basal 

 granules as in Nordstedt's fig., I.e. The most that could be seen 

 were five-six. These did not till up the breadth of the isthmus, 

 however, and in the largest single semicells, when tilted, I was 

 just able to discern nine granules across the isthmus, but nothing 

 more. 



Forma fontensis, n.f. (T.v. f.29). 



Forma pauUo minor quam forma typica; tumore basali granulis 

 in series distinctas, verticales 5 et horizontales 5-6 dispositis, 



