520 Philippine Journal of Science 



Fig. 12. A sexual coenobium between two asexual ones. The former con- 

 tains fifteen reproductive cells, of which thirteen are oogonia 

 and two are oospores. The asexual coenobium at the right 

 contains seven gonidia; two pairs of larger ones in the pos- 

 terior half of the coenobium (uppermost in the figure) and three 

 smaller gonidia in the anterior half. The coenobium at the 

 left contains two pairs of large gonidia in the posterior half, 

 one smaller gonidium in the anterior half, and a still smaller 

 anomalous cell like a gonidium at the posterior pole. X 100. 



13. An asexual coenobium with seven embryos. It shoAVs end and side 



views of bullet embryos, and a side view of a bowl embryo 

 with the gonidia (8) obviously outside of the bowl. X 100. 



14. An asexual coenobium with three pairs of gonidia. x 200. 



15. An asexual coenobium with one gonidium and six embryos which 



are all in the bullet stage, the daughter gonidia being closely 

 clustered about the posterior pole of the coenobial cavity. 

 X 200. 



16. The same coenobium in slightly different focus. X 100. 



17. An asexual coenobium containing seven embryos, in each of which 



the gonidia have become separated. X 100. 



TEXT FIGURE 



Fig. 1. Phylogeny of the Volvoceae. 



