l8 NATURAL HISTORY AND TOPOGRAPHY OF GROTON, MASS. 



Dock. Patience. Rumex patentia. Fields and waste places. 

 May 1 6. 



Great Water-Dock. Rumex Britannica. Meadows. August i. 



Curled Dock. Rumex crispus. Waste places. May 30. 



Bitter Dock. Rumex obtusifolius. Waste places. June 9. 



Sheep Sorrel. Rumex Acetosella. Fields and waste places. 

 May 16. 



Knotweed. Polygonum aviculare. Waste places. July 10. 



Polygonum amphibium. Mud. July 30. 



Lady's Thumb. Polygonum Persicaria. Damp waste places. July 1. 



Common Smartweed. Water-Pepper. Polygonum Hydropiper. 

 Wet places. July 15. 



Halberd-Leaved Tear-Thumb. Polygonium arifolium. Low 

 woods. August 10. 



Arrow-Leaved Tear-Thumb. Polygonum sagittatum. Low woods. 

 June 12. 



Wild Ginger. Asarabacca. Asarum Canadense. Rocky Hill. May 5. 



Spice-bush. Benjamin-bush. Lindera Benzoin. North End. 

 March 30. 



Bastard Toad Flax. Comandra umbellata. North End. May 29. 



Cypress. Spurge. Euphorbia Cyparissias. Roadsides and waste 

 places. July 26. 



Hop. Humulus Lupulus. Fields and roadsides. May. 



Wood-Nettle. Laportea Canadensis. Black Pond. July 1. 



Sweet Fern. Myrica asplenifolia. Rockwood's pasture. May 12. 



Wild Hazel-Nut. Corylus Americana. Hedges and roadsides. 

 March 23. 



Beaked Hazel-Nut. Corylus rostrata. Our orchard. Rare. 

 March 23. 



Hornwort. Ceratophyllum demersum. Wrangling Brook. Nashua 

 River. August 1. 



Eel-Grass. Tape Grass. Vallisneria spiralis. Nashua River. 

 August 1. 



Coral-Root. Orchid. Corallorhiza innata. Black Pond. May 30. 



Coral-Root. Orchid. Corallorhiza multiflora. Our woods. August 



T 7- 



Ladies' Tresses. Orchid. Spiranthes Romanzoffiana. Black Pond. 

 August 1. 



Ladies' Tresses. Spiranthes cernua. Fields. August 20. 



Ladies' Tresses. Spiranthes gracilis. Duck Swamp. July 23. 



