850 AUSTRALIAN FRESHWATER PLANKTON, 



This species has oval cells instead of the usual spherical ones. 

 A family of eight coenobia, of eight cells each, was noted. 



Var. AMPLA, n var. (PI. lix., f. 16). 

 Coenobiura maximum, cellulas permultas includens. 

 Ccenob. diam. 145; cell. long. 10-12, lat. 6-8/x. 

 Auburn. Cum priori. 



A form with coenobium much larger than usual, and enclosing 

 a very large number of cells. 



EXPLANATION OF PLATES LVI.-LIX. 

 Plate Ivi. 

 Figs. 1-4. — Carteria muUiJflis (Fresen.) Dill, forma; ( x 6b0). 

 Figs. 5-7. — C. scrohicidat.a, n.sp. ; ( x 660). 

 Fig.8. — C. scrohiculata var. ovalis, n.var. ; ( x 660). 

 Fig.9. — C. australis, n.sp.; ( x 1000). 

 Fig. 10. — C. australis var. orata, n.var.; ( x 1000). 

 Figs. 11, 12. — Ghlamydomonas gloeocystiformis Dill, formae; (11) x 1000, 



(12) X 1330. 

 Fig. 13. — CM. pisiformis var. attenuata, n.var.; ( x 1000). 

 Fig. 14. — CM. pisiformis var. glaocystiformis, n.var.; ( x 500). 

 Fig. 15. — CM. (jlohulosa var. pertusa, n.var.; ( x l(X)O). 

 Fig. 16. — CM. monadina var. ovalis, n.var.; ( x 1000). 

 Yig.n.—CM. globom Snow; ( x 1330). 

 Fig. 18. — CM. Lismoreiisis, n.sp.; ( x 2000). 

 Figs. 19, 20. — CM. Lis7nore7i.ns var. omta, u.var. ; ( x 2700). 

 Figs.21, 22.— P/i.aco<t6s bidlatus, n.sp., (6) side, (c) end; (21) x 1000, 



(22) X 1330. 

 Fig.23. — P. bidlatus var. conicus, n.var.; ( x 1000). 

 Yigs.'Zi, 25.— Ptero77i07ias cruciata, n.sp., (24) front, (25) side, (a) end; 



( X 1000). 

 Fig.26.— P<. cruciata var. ptdchra, n.var., (a) front, (b) side, (c) end; 



( X 1000). 



Plate Ivii. 

 Fig.l. — Ptdiastrum tetras var. Jluriatde, u. var.; ( x 660). 

 Fig.2. — P. tetras var. apiculatum, n.var.; ( x 660). 

 Fig.3. — Crucigenia tefrapedia var. ornata, n.var.; ( x 1330). 

 Fig. 4. — C. triangularis Chodat; ( x 660). 

 Fig.5. — C. quadrata var. secta, n.var.; ( x 1000). 

 Fig.6. — Tetrastrum elegans, n.sp.; ( x 1000). 

 Fig.7. — T. elegam var. dentatum, n.var.; ( x 1000). 

 Pig. 8. — Gcelastrum a-enatum var. cubicu7n, n.var.; ( x660). 



