47° HALORAGIDACEAE 



2. Myriophyllum [Vaill.] L. 



Carpels smooth. 



Flowers on emersed spikes. 



Floral leaves shorter than the spikes. I. M. spicatum. 



Floral leaves longer than the spikes. 2. M. verlicillatum. 



Floral leaves reduced to minute bracts. 3. M. tenellum. 



Flowers on both emersed and submersed stems. 4. M. humile. 



Flowers only on submersed stems. 7. M. proserpinacoides. 

 Carpels rough or tuberculate. 



Floral leaves ovate or lanceolate, serrate. 5. M. heterophyllum. 



Floral leaves linear, pectinate. 6. M. pinnatum. 



i. M. spicatum L. In deep water: Newf. to the N. W. Terr., 

 Md., Iowa, Kan. and Col. Also in Europe and Asia. 

 Conn. Litchfield Co. 



N. Y. Known only from Dutchess Co. northward. 

 N. J. Doubtfully reported from Passaic Co., otherwise unknown. 



2. M. verticillatum L. In pools, etc. : Que. and Ont. to N. J. and 



Pa., Minn, and Cal. Also in Europe and Asia. 

 Conn. Scattered over most of the state, but rare. 

 N. Y. Dutchess Co., northward. 

 Pa. Bucks Co. 



3. M. tenellum Bigel. Sandy bottoms of ponds and streams: 



Newf. to N. J., Pa. and Mich. 



Conn. Rare in New London and Litchfield counties, doubtless 



in the intervening territory, but not reported. 

 N. Y. Known only from L. I., S. I., and the Hudson Valley below 



the Highlands. 

 N. J. Known only along the Delaware in Gloucester and Camden 



counties and along the coast in Monmouth and Ocean counties, 



not in the pine-barrens. 

 Pa. Near Twelve Mile Pond, Pike Co. 



4. M. humile (Raf). Morong. In ponds: Me., R. I. to Md. and 



111. 



Rather common near the coast and in the pine-barrens, decreasing 

 and very local northward. 



5. M. heterophyllum Michx. In ponds: Ont. and N. Y. to 



Fla., S. Dak., Tex. and Mex. Very rare. 



N. J. Near Hammonton, Atlantic Co. 

 Pa. Bucks Co. 



6. M. pinnatum (Walt.) B. S. P. In ponds: R. I. to Fla., Kan., 



La., Tex. and Panama. 



