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few small red plates, shaped like paralleloerams. On the addition 
of sulphuric acid of 66'/, or 76 °/, the orange-yellow erystals become 
blue without any deliquescence to globules or solution being observed. 
This takes place when sulphuric acid of 95 °/, is used. The small 
red erystals, shaped like parallelograms are not so quickly colcured 
blue as the orange-yellow ones or a more concentrated acid must be 
applied in order to colour them blue. The crystals also behave dif- 
ferently with respect to phenol glycerine. The orange-yellow quickly 
dissolve in it whilst the red remain undissolved. The orange-yellow 
crystals behave therefore like xanthophyll-erystals and the red ones 
like carotin-crystals. The investigation of the green aplanospores 
therefore gives no special result. Two carotinoids are found to accom- 
pany chlorophyll, an orange-yellow one and in small quantity a red 
one, as is usual in green plants. 
In those aplanospores which are more or less red in colour there 
are found after treatment with Morrscu’s reagent reddish-violet crystal 
aggregates and, frequently, curved band shaped crystals. I now 
leave out of further consideration the small red crystals shaped like 
parallelograms. The crystals do not seem to be so easily separated 
out in the red aplanospores as in the green ones. It is advisable to 
allow Morrscn's reagent to act for at least some days in order to 
decompose the fatty substance which tenaciously retains the colouring 
matter. If any of the fat remains behind, the investigation becomes 
more difficult in consequence. 
By means of sulphuric acid of 66'/, the reddish-violet crystals 
become blue, also with 76°/, sulphuric acid, but in this case the action 
is accompanied by partial solution, which sometimes is preceded by 
deliquescence. The surrounding medium becomes blue. The behaviour 
of the reddish-violet crystals towards sulphuric acid of varying 
strength is therefore different from that of the orange-yellow crystals. 
In a solution of phenol in glycerine (8 to 1) the reddish-violet 
crystals easily dissolve, and colour the solvent dark reddish-violet. 
The crystals were not at one time of an orange-yellow colour, 
and at another time reddish-violet, but in many cases they oscillated 
between the two colours. Orange-yellow and reddish-violet crystals 
were never observed side by side in the same cell. These facts and 
the solution in 76 °/, sulphuric acid, as described, led me to suppose 
that the reddish-violet crystals were perhaps mixed erystals composed 
of two carotinoids. [ then tried to separate them with solvents, and 
succeeded. The crystals often completely dissolve in acetone or 
absolute alcohol; the orange-yellow carotinoid remains in solution, 
but the other quickly separates out again in the cells in the form 
