20,5 Shaw: Janetosphaera and Volvox 491 
in what was then German East Africa. These were illustrated 
by photomicrographic figures of two male, one mixed (male and 
asexual), and one female coenobium, the latter containing 
mature oospores, and by a drawing of a ripe oospore. 
The adult coenobia were described as large and globose, meas- 
uring 1,125 to 1,240 » in diameter. The figures show the mixed 
and male coenobia (West, ’18) as somewhat elongated, and give 
' measurements of 1,090 to 1,240 » in width and 1,340 to 1,400 » 
in length. The number of cells was stated to vary from about 
25,000 to rather more than 50,000. Estimates of the cells shown 
in the figures of male and mixed coenobia range between 32,000 
and 35,000. The protoplasts of the somatic cell are 4 to 6.5 » 
in diameter. In surface view they are somewhat angular and 
appear to possess relatively stout protoplasmic processes con- 
necting them with their neighbors. The spaces between neigh- 
boring protoplasts are narrower than the breadths of the 
protoplasts. Thus there is a dense crowding of the protoplasts 
that gives the coenobia a very robust appearance. 
The number of gonidia formed in a coenobium was regularly 
eight. From the micrographic figures showing daughters, it 
appears that the gonidia are very regularly and symmetrically 
arranged; four are equidistant in a transverse plane through or 
very slightly in advance of the equator, and the four others al- 
ternate with the first four in a transverse plane midway between 
the equator and the posterior pole. 
The daughter coenobia were set free when each had a diameter 
of about 370 ». At this stage the protoplasts apparently touched 
one another, and they continued to do so almost up to the time 
when the coenobia reached a diameter of 800 to 850 p. The 
first formation of daughter coenobia was observed in mother 
coenobia of that size. From this it appears that the gonidia are 
not differentiated in size from the somatic cells until some con- 
Siderable time after the birth of the coenobia in which they are 
formed. 
The oogonia and androgonidia are produced in different 
coenobia, though gonidia and androgonidia occur in the same 
coenobium (West, 18, fig. 2). 
The number of oogonidia or oospores in a coenobium was stated 
to range from 120 to 150 and to average 128. The figure (West, 
18, fig. 8) shows them to be absent about the anterior pole. 
The oospores are shown and described as densely clothed with 
strong conical spines. Their average diameter without the 
Spines is given as 44 » and the length of the spines 11 to 12 ». 
