ftT G. I. PLAT FAIR. 517 



oblique cleft. In sideview, both cell-wall and green cell are seen 

 to be compressed, the cell-wall cleft above and the two heads 

 turned outwards. No pyrenoid in the specimens observed. 

 Nucleus and stigma not visible, the membrane strongly rufescent. 



Genus C h l a m y d o m o n a s Ehr. 

 Chlamydomonas reniformis, n.sp. (PL Iv., f. 9, 10). 



Cellula compressa; fronte visa reniformis ubique rotundata, 

 pone indentata. A latere compressa, ovalis vel ovata. Membrana 

 tenuissima glabra, cytoplasmati arete adhaerens. Pyrenoidis 

 nulla nee stigma (in specimine notato). 



Diam. 10^, alt. 8-|//.. Lismore (312). 



A very curious form, of which I saw but one specimen. It 

 ver}^ much resembles Garteria rugulosa, and might possibly be a 

 young form of that species. The flagella (2) were very distinct 

 and unusually thick. On the other hand, the cell-wall is closely 

 adherent to the cytoplasm, perfectly smooth and hyaline. 

 Chlamydomonas Lismorensis v. gracilis, n.var. (Pl.lv., f.ll). 



Cellula anguste cylindracea, pone rotundata, fronte conica, 

 lateribus parallelis. Chloroplastis parietalis ; pyrenoid e nulla 

 visa; stigmate distincto inter apicem et medium posito; granulis 

 paucis juxta apicem. 



Long. 9J, lat 2J/x. Lismore (345). 



The type (these Proceedings, 1917, p.827, PI. Ivi., f.l8) is ob- 

 long-cylindrical with rounded ends, and proportionately broader. 

 This form is narrower, and conical in front. Chloroplast bright 

 green, homogeneous, parietal; no pyrenoid seen; stigma wick- 

 shaped, very distinct, halfway between the apex and the middle. 



Chlamydomoxas rotula, n.sp. (PI. Iv., f. 12). 



Cellula oblonga (vel globosa ?) ubique rotundata; in media 

 cellula pyrenoide magna; chloroplastide in discos teiiues parietales 

 multos diviso, discis singulis ad pyrenoidem taenia chlorophyllacea 

 connectis; stigmate nullo viso. 



Long. 19-21, lat. 15; pyrenoid. 6/y.. Lismore (345). 



Easily recognised by reason of the extraordinary disposition of 



