264 Campbell . — On Pilularia globulif era, L. 
Fig. 6. Transverse section near the base of the first leaf of an embryo nine days 
old. i, intercellular spaces. Alcohol-gen tian-violet-preparation. x 300. 
Fig. 7. Vertical section of an embryo thirteen days old showing the second root. 
R 2 . x 300. 
Fig. 8. The second leaf of the same embryo, x 300. 
Fig. 9. Longitudinal section through the apex of a young plant that had four 
fully-developed leaves, s, Apex of the stem. L , Z 1 , young leaves, r, a young root, 
x about 100. 
Fig. 10. Transverse section of a leaf of the same embryo, x 48. 
Fig. 11. Vascular bundle of the same, x 300. 
Figs. 12-13. Stomata from the first leaf. x 300. Fig. 12 in longitudinal 
optical section Fig. 13 from the surface. 
