20, 5 Shaw: Janetosphaera and Volvox 501 
on the type slide. In this there are two bodies that appear to be 
diseased or parasitized daughters of about 73 and 88 » diam- 
eter, in a coenobium of 680 by 760 ». This coenobium has a 
large distinct vegetative forward area. The two daughters 
occupy positions corresponding to those of two adjoining mem- 
bers of a posterior quartet in a typical coenobium with eight 
daughters. The quarter sphere occupied by the two daughters 
is free from oospores. The latter are distributed, then, in the 
other posterior quarter sphere and around the equatorial margin 
of the forward half of the coenobium; that is, between the 
equator and the forward vegetative area. About one-third of 
the oogonia appear to have been unfertilized, for they are de- 
ficient in reserve material and have formed no spore walls. 
Those that have formed spore walls have developed them in 
considerable variety. 
The variation in the spore walls of the aforementioned coe- 
nobium are noteworthy. A few are almost smooth; some are 
smooth with a few scattered rounded warts; a few are wavy 
to a very marked degree; and many have a smooth wall with 
numerous but not crowded conical warts or rounded warts. 
Some of these are of the form represented by Janet (14, p. 7, 
fig. 1) for Volvox globator. They vary in size, but an average 
one measures about 42 » over all and 34 » without the warts, the 
latter being about 4 » high or less. On some spores the warts 
are rounded and on others conical. 
A COMPARISON OF THE SPECIES OF VOLVOX 
Considering only the species here classified as Volvox there 
are five; Volvox globator of Europe, V. perglobator of North 
America, V. rousseleti of Africa, and V. merrilli and V. barbert 
of the Philippine Islands. 
To facilitate a comparison of these species some of their 
characters have been set down in parallel columns in Table 1. 
The data here used are not all uniformly representative of the 
species to which they pertain, but it is thought that they will 
Serve as a good first approximation. 
The best means of distinguishing between the two Philippine 
species of Volvox is by the size and form of the somatic cells 
of the coenobia. Those of V. merrilli are relatively large, wider 
than high, and stellate, much like those shown in Meyer’s 
drawings of those of V. globator reproduced herewith as text 
figs. 8.and4. Those of V. barberi are smaller, higher than wide, 
and vary from more or less stellate in younger coenobia to 
Ovoid about the forward pole and pyriform about the hinder 
