110 MIDDLESEX FLOEA. 



J. articulatus, L. 



Gioton iind T.owell (Dr. C. W. Swan) ; Medford (Wm. Boott). 

 J. militaris, Bigel. Bayonet Rush, 



Tewksbiuy (B. D. Greene) ; Dracut and Westford (Dr. C. W. 



Swan) ; Concord (Walter Deane) ; Bedford (C. W. Jenks). 

 J. acuminatus, Michx., var. debilis, Engelm. 



"Issue of Mystic river" (Wm. Boott; specimen in herb. of). 

 J. acuminatus, Michx., var. legitimus, Engelm. 



Lowell (Dr. C W. Swan) ; Medford and Somerville (C. E. Perkins) . 

 J. nodosus, L. 



Mfdford (Wm. Boott; specimen in herb. of). 

 J. scirpoides, Lam. 



Medford (Wm. Boott; specimen in herb. of). 

 J. scirpoides. Lam., vav. polycephalus^ Engelm. 



Tewksbury (B. D. Greene), specimen in herb. B. S. N. H. Un- 

 doubtedly adv. from farther South. 

 J. Canadensis, J. Gay, var. longicaudatus, Engelm. 



Generally distributed. 

 J. Canadensis, J. Gay, var. coarctatus, Engelm. 



Billerica and Marlboro (Dr. C. W. Swan) ; Somerville (C. E. 



Perkins). 



PONTEDERlACE>E. PICKEREL-WEED FAMILY. 



PONTEDERIA, L. 



P. cordata, L. Pickerel-weed. 

 Common. 



COMMELYNACE^. SPIDERWORT FAMILY. 



Tradescantia, L. Spiderwort. 



T. Virginica^ L. 

 Ashland (F. S. Collins), growing along the track of the B. & A. 

 R. R., remote from houses. Adv. from farther South. 



XYR1DACE>E. YELLOW-EYED-GRASS FAMILY. 



Xtris, L. 



X. flexuosa, Muhl. Yellow-eyed-grass. 

 Nagog Pond, Acton, Aug., 1882 (W. H. Manning) ; Ashland (Rev. 

 Thos. Morong). 



