"December 1970."

Introduction. pp. 1-4. Group 1. Plants with upright or upslanted leafless stems; or similar plants with long, narrow leaves coming from the lower part of the stems; flowers usually individually inconspicuous, but crowded and numerous. pp. 5-22. Group 2. Plants with upright or upslanted stems with grass-like leaves on two sides (one plane); flowers individually inconspicuous between scales which overlap in two rows to form spikelets, the spikelets clustered toward the top of stems. pp. 23-36. Group 3. Plants with upright stems with grass-like leaves on three sides; flowers individually inconspicuous between scales which usually overlap in several rows to form spikelets, the spikelets clustered toward the top of stems. pp. 37-45. Group 4. Plants with upright, sprawling, or horizontal stems with singly placed, non-grasslike, lance-shaped or wider, untoothed leaves; flowers clustered at the end of stems or single or clustered at the base of leaves. pp. 46-55. Group 5. Plants with upright, sprawling, or horizontal stems with paired, whorled, or otherwise clustered, lance-shaped or wider, untoothed leaves; or plants with leafless stems and paired or whorled branches; flowers single or clustered at the end of stems, in stalked heads along stems, or single or clustered at the base of leaves. pp. 56-69. Group 6. Plants with both their lance-shaped or wider, untoothed leaves and the stalks of their solitary flowers or flower clusters coming from underground stems or underwater sterms. pp. 70-86. Group 7. Plants with tooth-edged to deeply divided leaves or leaflets. pp. 87-94. Index. pp. 95-99.