CHLOROPHYCEA 187 
examined fresh from the surface, and becomes 
coloured brown with iodine solution, but with iodine 
and sulphuric acid no blue colour was observed. 
They were never observed to colour with carmine 
solution. When the calcareous parts are removed by 
dilute acids a small gelatinous sphere remains, in the 
outer layer of which the Coccoliths or Rhabdoliths 
were embedded.” (‘‘ Challenger Reports.” Narrative, 
vol. 1. p. 989.) 
