510 Philippine Journal of Science 1919 
The foregoing descriptions form the basis for the following: 
DIAGNOSIS OF GENUS AND SPECIES 
CAM PBELLOSPH AERA genus novum 
( Volvocaceae , V olvoceae) 
Body a spherical or spheroidal coenobium of biciliate cells 
which contain chloroplasts. The cells appear to lie in the pe- 
riphery of a gelatinous matrix surrounded by a hyaline envelope 
through which the cilia extend. Somatic protoplasts globose or 
ovoid, each enclosed in a thick gelatinous membrane which is 
prismatic in form with truncate interior end and more or less 
rounded exterior end. No protoplasmic filaments connecting the 
protoplasts. Asexual reproduction by gonidia, differentiated in 
early embryonic stages, which migrate from without into the 
interior of the embryo through the phialopore before closure. 
The gonidia are distributed and held in place by their thickened 
gelatinous walls. They develop to relatively large size before 
segmentation. Sexual reproduction by oospores which are more 
numerous and smaller than the gonidia, and are usually formed 
in the same coenobia with antheridia. Antheridia less numerous 
than the oogonia, in the form of platelets. Spermatozoids elon- 
gate, probably with terminal cilia. 
CAMPBELLOSPHAERA OBVERSA sp. nov. 
Coenobium spheroidal or more or less elongate; dimensions 
commonly less than 500 t x. Number of somatic cells mostly be- 
tween 2,000 and 3,000 ; protoplasts globose, about 5 ^ in diameter; 
cell membranes very convex on the outer side. Gonidia, usually 
8, 7, or 6, sometimes fewer, seldom more, arranged in quartets, 
or pairs, or a quartet and one or two pairs, in graded sizes ar- 
ranged symmetrically with respect to the polar axis of the coe- 
nobium; those of the posterior pair or quartet the largest and 
segmenting first, those of the anterior pair or quartet smallest 
and segmenting last. Gonidia, 15 to 18 fi in diameter when 
differentiated, attaining diameters of 50 to 90 /* before dividing. 
Daughter coenobia developing their gonidia to large size before 
birth. All daughters born through one hole formed by loss of 
somatic cells in a circular area about the posterior pole. Asexual 
and sexual daughters formed in the same mother coenobia. 
Sexual coenobia monoecious. Gametangia more numerous and 
smaller than the gonidia, largest number, about 30; diameters, 
about 12 to 14 /x when first differentiated, becoming about 29 to 
37 ix in diameter; the smaller becoming antheridial platelets of 
128 sperms, the larger more numerous and becoming oogonia. 
