Details of Plate 9. 

 Figs. 



1. Dunaliella salina (a), D. viridis (c), and Pyrarnimonas sp? (6) in their relative numbers, in 



brine from which salt (NaCl) is crystallizing. X475. 



2. A colony of D. viridis (gr) formed by division on 1 per cent agar-agar in 1.190 brine, 8 days 



after inoculating plate. Granules are starch. D. salina (br) dividing. X440. 



3. D. salina dividing, direction of division apparently independent of direction of light. X440. 



4. D. viridis (a), colony of 8 cells, at 11 a.m., 7 days after inoculation on 1 per cent agar-agar 



plate of brine of 1.050 sp. gr. X440. 

 5a. Same colony, 9 cells, at 4 h 20™ p.m. same day. X440. 



b. Same colony, 15 cells, at ll h 45 m p.m. next day. X440. 

 66.' Week-old colony, 4 cells, at 4 b 40™ p.m. on 1 per cent agar-agar in 1.050 brine. 



b'.' Same colony, 5 cells, at ll h 30 m a.m. next day. X440. 

 la. Same colony, 5 cells, at 3 h 45 m p.m. same day. X610. 



b. Same colony, 7 cells, at 3 h 40 m p.m. next day. X440. 



c. Same colony, 7 cells, at 10 h 40 m a.m. next day. X440. 



So. Same colony, 15 cells, as in fig. b, but at 3 b 50 m p.m. of same day. 



6. Same colony, 16 cells, at 3 h 50™ p.m. of next day. X440. 



c. Same colony, 16 cells, at 10 h 55 m a.m. of next day. X440. 

 9. Cell division induced within 24 hours by transfer from brine of 1.200 sp. gr. to agar-agar 

 brine of 1.190. X610. 



10. Stages in encysting in a gradually d^nng culture, a, at ll h 17™ a.m.; 6, ll h 40 m a.m.; c, 



same hour next day; d, two days after c; e, two days after d. X440. 



11. Germination of resting cells on agar-agar plate following the addition of water to the 



saturated brine. X440. 



