ZANICHELLIACEAE. 13 



4. Potamogeton Zizii M. & K. In lakes and streams from Que. to Ida., Fla. 

 and Texas. Cerro Summit. 



5. Potamogeton heterophyllus Schreb. In still or flowing water from Lab. 

 to B. C., Fla. and Calif. Alt. 5000-6000 ft. Near Boulder. 



6. Potamogeton lucens L. In ponds and lakes, from N. Sc. to Fla. and 

 Calif. Cottonwood Lake. 



7. Potamogeton Richardsonii (Bennett) Rydb. (P. perfoliatus lanccolatus 

 Robbins) In lakes, ponds and slow streams from Newf. to Alaska, Del. and 

 Calif. Alt. about 8000 ft. Tomichi River. 



8. Potamogeton foliosus Raf. In streams and ponds from N. B. to B. C., 

 Fla. and Calif. Alt. 4000-9000 ft. North Platte River, below Hebron ; Grand 

 River, Sulphur Springs; Platte River, Denver. 



9. Potamogeton pusillus L. In slow streams and ponds from N. B. to B. C., 

 N. C. and Calif. Alt. 4000-8000 ft. Base of Pike's Peak; Brantly Canon, 

 Las Animas Co. ; Alamosa. 



10. Potamogeton filiformis Pers. In ponds and lakes from Anticosti to 

 B. C., N. Y. and Colo. Alt. 4000-9000 ft. Twin Lakes; Walsenburg; Grand 

 Lake. 



11. Potamogeton interior Rydb. (P. marinus occidentalis Robbins) In 

 lakes and slow streams from Alb. to Colo, and Nev. Alt. 6500-10,000 ft 

 San Luis Valley; Ironton Park, nine miles south of Ouray; Tomichi River; 

 Gunnison ; Hamor's Lake, Durango. 



12. Potamogeton pectinatus L. In fresh, alkaline or salt water from N. B. 

 to Alaska, Fla. and Low. Calif. Alt. 4000-10,000 ft. Twin Lakes; New 

 Windsor; lake near Ft. Collins; Grizzly Creek; Trapper's Lake; Lee's Lake, 

 Ft. Collins. 



2. ZANICHELLIA L. ZANICHELLIA. 



i. Zanichellia palustris L. In fresh and alkaline ponds and streams especi- 

 ally with sandy bottoms from Mass, to Wash., Fla. and Calif.; also in the 

 Old World. Alt. 4000-9000 ft. Ft. Collins; Platte River, Denver; stream 

 twelve miles below Grand Lake; swamp along Poudre River. 



Family 14. NAIADACEAE Lindl. NAIAS FAMILY. 

 i. NAIAS L. NAIAS. 



i. Naias guadalupensis (Spreng.) Morong. In brackish and alkaline water 

 from Kans., Nebr. to Ore., Fla. and Texas ; Tropical America. Lee's Lake, Ft. 

 Collins. 



Order n. ALISMALES. 



Petals similar to the sepals ; anthers long and narrow ; carpels coherent. 



Fam. 15. SCHEUCHSERIACEAE. 



Petals different from the sepals, in ours white ; anthers short and thick ; carpels 



not coherent. 



Fam. 16. ALISMACEAE. 



