By G. I. PLAYFAIR. Ill 



This species is half as large again as the foregoing and very different in 

 appearanee. It is elliptical-oval, not ovate, but the minute emarginatiou in 

 front may still be noted. The memljrane is smooth and hyaline, showing no 

 sign whatever of markings or setae. 1 examined a specimen with the l/12th inch 

 homogeneous immersion lens; the internal organisation is exactly as in Si/tinra 

 or Mallomonas, the anterior third consisting of very finely granular protoplasm, 

 the posterior two-thirds of a globe of clear, transparent, homogeneous material 

 surroundeil by large amylaceous granules, the whole being enclosed liy two deli- 

 cate parietal chromatoi^hores. The colour of the latter was very distinct, being 

 neither yellow-green nor chlorophyll-green, nor brownish-green, nor blue-green, 

 l)ut a deeji gray-green. Very little reliance, however, can be placed on the 

 colour of the cbromatopliores in the Chrysom-onadineae as a study of Crypto- 

 monas soon shows. Two very delicate flagella noted, which seems to separate the 

 organism from Mallomonas ; I was not able to detect the pulsating vesicles, but 

 from 2 to 4 will probably be found towards the hinder end of the cell. 



Fam. TESSELLARIACEAE. 



Genus Tessell.\ria Playfair. 



Tessellaria volvocina Playf. 



See description and figures in "Freshwater Algae of the Lismore District" 

 (These Proceedings, 1915, p. 315, PI. xlv., f. 6, 7, under Tessella). Also a fur- 

 ther note in "New and rare freshwater Algae" {ibid., 1918, p. 508, PI. Ivi., f. 4). 

 I have nothing to add to these notices except to remark tliat the organism is 

 not as rare as I thought at first. I have obtained plenty during the last few 

 years. 



Fam. HYMENOMONADACEAE. 



Genus Synura Ehrenberg. 

 Synura virescens (Bory). (PI. ii., figs. 16 — 18). 



Coenob. diam. ad. 137; cell. long. 22 — 24, lat. 7 — 9fj,. 



Wyrallah; Lismore (242, 314). 



Syn. Uvella virescens Bory, Encycloj)., 1824 (teste Dujardin, p. 301); 

 for figure see Kent, PI. xxii., f. 24 — 2ti, but tlie cliromatophores are contracted. 

 In "Freshwater Algae of the Lismore District," p. 314, I recorded this species 

 as Synura uvella Ehr. All the authors, however, who have figured the latter, 

 show the cells as clothed with line setae; cf. Stein, T. xix., Abt. i., f. 1 — 7; Kent, 

 PI. xxiii., f. 1, 2; Senn. p. 162, f. 116a; Klebs, Flagellatenstudien (Senn's fig. 

 A2) and others. 



This makes it plain that if S. uvella is found here it must be very rare, as 

 in twenty-five years I have never seen a specimen of a Synura showing setae. 

 This smooth species, S. virescens Bory, however, is occasionally met with, though 

 by no means common either. I figure three forms which may all be noted either 

 separately or intermingled in the same coenobium. The membrane is very thin 

 and does not show as a double line; the chromatophores lie close to it. No stigma 

 noted, but I think that one or more minute stigmata may occasionally be found, 

 though rarely, in all forms of Synura and Mallomonas. Stokes (op. cit., p. 117) 

 records this species from U.S.A. 



