56 UNIVERSITY OF MISSOURI STUDIES [204 



30. P. heterophyllus Schreb. Various-leaved pondweed. 

 Near Boulder, 5100-6000 ft. (Rydberg). 



North America, except extreme north: Europe. 



31. P. foliosus Raf. [P. pauciflorus Pursh]. Leafy pond- 

 weed. 



Streams and ditches east of Boulder, 5100-5500 ft. (Dan. 

 iels, 736). 



New Brunswick to British Columbia; Florida to Cal- 

 ifornia. 



32. P. Spirillus Tuckerm. Spiral pondweed. 



Swales along railroad between Boulder and Marshall, 

 5400 ft. (Daniels, 486). Not included in Rydberg's Flora of 

 Colorado. 



Nova Scotia to Minnesota; Virginia to Colorado. 



33. P. pectinatus L. Fennel-leaved pondweed. 

 Owen's lake; Boulder lake, 5300 ft. (Daniels, 681). 

 North America: Europe. 



24. ZANICHELLIA L. 



34. Z. palustris L. Marsh Zanichellia. 



Owen's lake; Boulder lake, 5300 ft. (Daniels, 682). Red- 

 rock lake, loioo ft. (Ramaley & Robbins). 

 North Temperate Zone. 



Order 8. ALISMALES. 

 Family 11. ALISMACEAE D C. Water-plantain family. 



25. AEISMA L. Water-plantain. 



35. A. Plantago L. Common water-plantain. 



Bogs west of Marshall ; swales, ditches, streams, and ponds 

 east of Boulder, 5100-6000 ft. (Daniels, 424). 

 Northern Hemisphere. 



26. SAGITTAEIAL. Arrowhead. 



36. S. arifolia J. G. Smith. Arum-levvved arrowhead. 

 With the preceding, 5100-6000 ft. (Daniels, 441). 

 Quebec to British Columbia; Maine and Michigan to 



New Mexico and California. 



