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, 1 0100 ft. (Ramaley & Robbins). 

 North Temperate Zone. 



Order 8. ALISMALES. 

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



25. ALISMA 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-leaved arrowhead. 

 With the preceding, 5 100-6000 ft. (Daniels, 441). 

 Quebec to British Columbia; Maine and Michigan to 



New Mexico and California. 



