504 
Philippine Journal of Science 
1919 
there is a small percentage of specimens of three other species 
of Volvocaceae, including some of Volvox africanus West, a 
species of similar dimensions. The mother coenobium of speci- 
men 22 (Plate II, fig. 10) measures 230 by 270 n, and has somatic 
protoplasts of about 5 /x diameter and cell diameters of about 
9 fx, the number of cells being about 2,640. The asexual daughter 
measures 95 by 105 ^ and contains seven gonidia. Of these 
the smallest is 16 by 18 and the largest, 43 by 45 p. There 
are six sexual daughters. Of these the smaller near one (in the 
left side of the picture just above the middle) contains twenty- 
seven reproductive cells, of which eight are small and medium- 
sized, 11 to 12 pi, and nineteen are large, about 17 p. The larger 
near daughter (in the lower side of the figure) contains about 
twenty-nine reproductive cells of 15 to 18 fi. The other daughter 
with reproductive cells in plain view (the lower one on the left 
side of the photograph) contains about thirty-one reproductive 
cells of 15 and 18 p, mostly of the larger size. The three other 
sexual daughters have about the same number of reproductive 
cells, and all of the sexual daughters are elongated and free 
from reproductive cells in one end. A number of endophytic 
algae are prominent in the walls of the mother coenobium. 
Several other examples of mother coenobia, containing mixed 
broods of progeny differing in no significant particular from 
the one just described were found on the slides of the lot under 
consideration. 
A sexual coenobium with a smaller number of reproductive 
cells occurs as a daughter in the mother coenobium shown in 
Plate II, fig. 11. This specimen (No. 23) is on one slide (No. 
1) of a lot prepared from the same material as the type slide, 
but with the omission of the nigrosin stain. The mother coeno- 
bium measured, when the micrograph was taken in June, 1919, 
170 by 210 ft,. The somatic protoplasts were then about 5 p 
in diameter and the average cell width about 7.1 p . The esti- 
mated number of cells is 2,420. The mother contains one goni- 
dium, 52 by 53 p, four asexual embryos, and one sexual embryo. 
The most advanced asexual embryo is not much beyond the 
bullet stage. This embryo is elongate, 57 by 75 fx, almost pointed 
at the anterior end and blunt at the opposite end. It contains 
eight gonidia of about 18 p diameter. Four of these are closely 
grouped against the posterior wall of the coenobium, three lie 
almost a gonidial cell diameter in advance of the posterior 
quartet, and one is almost two diameters ahead of the quartet. 
Beneath this embryo there lies one in the typical bullet stage, 
