20 CHLORIS BOREALI-AMERICANA. 



except as to Pterospora ; and even with regard to this the obser- 

 vation greatly needs verification. 



Tab. II. Schweinitzia odorata, of the natural size. Fig. 1. A detached 

 flower, enlarged. Fig. 2. A flower, enlarged, with the sepals spread open. 

 Fig. 3. Unexpanded corolla, from an autumnal flower-bud. Figs. 4, 5. Two 

 sepals of the same. Fig- 6. Corolla laid open. Fig. 7. Magnified flower, 

 the calyx and corolla removed. Fig. 8. A stamen, more magnified. IHg. 9. 

 Pollen from young anthers, highly magnified ; the 2-4 grains still inclosed 

 in mother-cells. Fig. 10. Separate simple pollen-grains, equally magnified. 

 Fig. 11. Transverse section of the ovary. Fig. 12. A fertilized ovule, highly 

 magnified. 



