ILLUSTRATIONS 
[Photomicrographs of Volvox species, from specimens mounted in glycerine, taken by W. R. 
Shaw and E. Cortes at the Bureau of Science, Manila.] 
PLATE 1. VOLVOX MERRILLI SP. NOV. 
Fig. 1. The type specimen, a sexual coenobium with ninety-two nearly 
ripe oospores. xX 100. 
2. A portion of the surface of the same coenobium showing the soma- 
tic cells. x 400. 
3. Oospores below the surface of the same part of the coenobium 
that is shown in the preceding figure. x 400. 
PLATE 2. VOLYOX MERRILLI SP. NOV. 
Fig. 4. Another view of the same oospores with the shadows of the over- 
lying somatic cells not so dark and the spines shown with less 
depth of focus. x 400. 
5. Oospores in another coenobium of the same species. One is 
smaller than the typical spores, and resembles those of the 
other species. 400. 
PLATE 3. Fics. 6 TO 11, VOLVOX MERRILLI SP. NOV.; FIG. 12, VOLVOX BARBERI 
SP. NOV. 
Fic. 6. A young sexual coenobium showing three or four antheridia in 
different stages of formation. x 100. 
7. A small asexual coenobium with only two embryo daughters. 
x 100. 
8. A small coenobium with eight reproductive bodies, probably goni- 
dia. x 100. 
9. A sexual coenobium a little older than that of fig. 6, showing 
three or four antheridia in different stages of development, and 
numerous oogonidia that are a little larger than the somatic 
cells. x 100. 
10. A very small coenobium with three reproductive bodies that are 
gonidia and have each divided into eight cells. x 100. 
11. A half-grown asexual coenobium containing seven embryo daugh- 
ters. x 100. 
12. A very small coenobium without reproductive bodies. x 100. 
PLATE 4. VOLVOX BARBERI SP. NOV. 
Fic. 13. The type specimen; a sexual coenobium with two hundred twenty- 
four nearly ripe oospores. 100. 
14. A portion of the same coenobium showing in the middle the 
nearly ripe oospores, and in other parts somatic cells that are 
in focus because of the bent state of the coenobium wall. x 400, 
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