9:5 



ones from light, it is probablc — in analogy with wliat was 

 stated above under 7 for the oildroplets in amoebocytes — that 

 there must be some direct relation between the number of these 

 little globules and the number of dead algae, which, as known, is 

 also larger in sponges in darkness than in sponges in light (p. 59). 

 I shall mention only lateron, what relation this is. 



14. The little globules stainable by I are to be found somewhat 

 more numerous in the choanocytes of the flagellated chambers 

 than in the amoebocytes (Table 14). Also here one could ask 

 the question, which we put above in ï) for the oildroplets, if 

 perhaps not all these globules could have been captured from the 

 surrounding water by the sponge with the help of its choanocytes. 

 But also this question we must answer negatively, as these glo- 

 bules are about as numerous — or only a little less numerous — 

 in the choanocytes of sponges out of the lake-water or the water 

 from the conduit as in those of the sponges from the dirty canal 

 water (Table 14). 



15. As we saw under 13 that in the amoebocytes there is 

 some relation between the number of globules, stainable by I and 

 the number of dead algae, we might expect the same relation 

 in the choanocytes. This proves, however, not to be the case, as 

 the table below shows. 



choanocytic layer 



green sponge 



colourless sponge 



number of 

 glob. st. by I 



colourless algae 



number of 

 glob. st. by I 



colourless algae 



numerous 

 mass 

 » 



few 

 some 



» 



mass 



» 

 » 



few 



several 



rather numerous 



16. On p. 18 — 20 I have proved already, that the green sym- 

 biotic algae produce 0^ in light. 



