98 MIDDLESEX FLORA. 



SYMPLOCARPUS, Salisb. 



S. foetid us, Salisb. SKUNK CABBAGE. 

 Common. Mar.-Apr. 



ACORUS, L. 



A. Calamus, L. SWEET FLAG. 

 Common. June. Apparently native. 



LEMNACE>E. DUCKWEED FAMILY- 



LEMNA, L. 

 L. trisculca, L. 



Fresh Pond, Cambridge (Wm. Boott). Rare. 

 L. minor, L. DUCKWEED. 

 Common. 



SPEIRODELA, Schleid. 



S. polyrrhiza, Schleid. (Lemna polyrrhiza, L., Man.) 

 Common. 



TYPHACE>E. CAT-TAIL FAMILY. 



TYPHA, Tourn. 



T. latifolia, L. CAT-TAIL. 

 Common. June-July. 



T. angustifolia, L. SMALL CAT-TAIL. 



Winchester and Arlington (C. E. Perkins) ; Medford (G. E. Daven- 

 port). Common in these localities, but not reported elsewhere. 

 June-July. 



SPARGANIUM, Tourn. 



S. eurycarpum, Engelm. BUR-REED. 

 Rather common. 



S. androcladum, Morongin Torrey Bulletin, March, 1888. (S. 

 simplex, Huds., var. androcladum, Engelm.) Whitehall Pond, 

 Hopkinton (Rev. Thos. Morong) ; Medford (Wm. Boott) ; Waltham 

 (C. E. Perkins) ; et al. 



S. androcladum, Morong, var. fluctuans, Morong in Torrey 

 Bulletin, March, 1888. (S. simplex, Huds., var. fluitans, Engelm. , 

 Man.) A form closely approaching this variety was collected 

 at Whitehall Pond, Hopkinton, by Dr. C. W. Swan. 



S. simplex, Huds. 



Common. The form known as var. Nuttallii, Engelm., Man., 

 likewise common. 



