92 MIDDLESEX FLOKA. 



PARIETARIA, Tourn. 



*P. Pennsylvanica, Muhl. PELLITORY. 



Concord (Minot Pratt). This plant is out of its usual range, and 

 may possibly have been introduced by accident with other plants. 

 June- Aug. 



CANNABIS, Tourn. 



C. SATIVA, L. HEMP. 

 Rather common. July- Aug. Nat. from Eu. 



HUMULUS, L. 

 H. LUPULUS, L. HOP. 



Sparingly naturalized from the West. July. 



PLATANACE/E. PLANE-TREE FAMILY. 



PLATANUS, L. 



P. occidentalis, L. SYCAMORE. BUTTONWOOD. 

 Bather common. May- June. 



JUGLANDACE^. WALNUT FAMILY. 



JUGLANS, L. 



J. cinerea, L. BUTTERNUT. 

 Common. May. 



CARYA, Nutt. 



C. alba, Nutt. SHAGBARK HICKORY. 



Common. May-June. 

 C. tomentosa, Nutt. MOCKER-NUT. WHITE-HEART HICKORY. 



Not uncommon. May- June. 

 C. porcina, Nutt. PIGNUT or BROWN HICKORY. 



Common. May-June. 

 C. amara, Nutt. BITTERNUT HICKORY. 



Medford, Winchester, Belmont, et al. Less common than the other 



species.' May-June. 



CUPULIFER^E. OAK FAMILY. 



QUERCUS, L. 



Q. alba, L. WHITE OAK. 



Common. May. 

 Q. bicolor, Willd. SWAMP WHITE OAK. 



Common, especially in the eastern section of the county. May. 



