492 The Philippine Journal of Science 1922 
The androgonidia are described as very numerous in each male 
coenobium; usually there are several hundred. They are ab- 
sent about the anterior pole. The antheridia, though shown 
in the photomicrographs of three coenobia (West, ’18, figs. ty & 
and 7) ona scale of 50 diameters, were not described. Presum- 
ably they were regarded as so similar to the antheridia of the 
European species of Volvox as not to call for particular descrip- 
tion. This is unfortunate, because of the considerable variation — 
in the antheridia in the species of Volvox from other parts of the 
world. The spermatozoids, naturally, were not described, the 
material having been preserved in formalin. 
VOLVOX MERRILLI sp. nov. 
For the type of this species the specimen represented by 
Plate 1, figs. 1, 2, and 8, and Plate 2, fig. 4, has been selected. 
The specimen appears to have been fixed in a picro-nigrosin 
solution, which stained it lightly, and to have been mounted 
with others from the same collection under a sealed cover in 
glycerine, concentrated from a 10 per cent solution by evapora- 
tion. The mounting fluid is strongly tinged with picric acid. 
The upper and lower sides of the specimen as mounted re- 
quire a difference in focal adjustment of about 300 » as indi- 
cated by a Zeiss side-focus fine adjustment. Assuming a 
refractive index of 1.4 for the mounting medium, I estimate 
the thickness of the specimen at about 420 » The short and 
long diameters of the coenobium measure about 690 and 750 z, 
respectively. By a camera lucida, sketch method described in 
another paper (Shaw, ’18, p. 256) from a count of 62 cells in 
an area of 8,100 sq. » the number of cells in the specimen was 
estimated to be about 12,100. The spacing of the somatic cells 
is fairly uniform for any particular part of the colony, and 
they lie in tolerably regular rows of various curvatures. 
The average distance between the centers of the cells of this 
specimen is about 11 » in the equatorial region, about 18 » 
around the anterior pole, and very little less than 11 » near 
the posterior pole. 
The protoplasts are roundish, unequally angular, about 4 » 
in diameter. (In immature sexual coenobia the protoplasts 
measure 6 to 7 ».) Their outer ends are between 1 and 2 p» 
from the outer limiting membrane of the colony. Their pro- 
toplasmic processes proceed from below the middle of each. 
The outer surface of the colony is nearly smooth, though very 
slightly wavy about the anterior pole. No inner limiting mem- 
