134 BOTANY OF MICHIGAN 



Tahquamenon River near lower falls above Emerson. Plentiful at this 

 place. 



Potamogeton dimorphus Raf. Spiral pondweed. Tahquamenon River 

 near lower falls above Emerson. Plentiful. 



Najas jlexilis (Willd.) Rostk. & Schmidt. Slender najas. Ponds, 

 small lakes, and margins of slow streams. Plentiful. 



JUNCAGINACEAE. Arrow Grass Family 



Scheuchzeria palustris L. Scheuchzeria. Open boggy places through- 

 out. Abundant near Vermilion. 



Triglochin maritima L. Sea-side arrow-grass. Marshy open places 

 throughout. Frequent. 



Triglochin palustris L. Marsh arrow-grass. Damp open sandy ground 

 throughout. Plentiful at Vermilion. 



ALISMACEAE. Water-plantain Family 



Sagittaria latifolia Willd. Broad-leaved arrow-head. Muddy places, 

 and shallow water in ponds and ditches and slow streams throughout. 

 Common. 



Alisma planlago-aquatica L. American water plantain. In shallow 

 water, muddy places, and ditches throughout. Common. 



HYDROCHARITACEAE. Frog's Bit Family 



Elodea canadensis Michx. Waterweed. Ponds, small lakes, and 

 slow streams. Plentiful throughout. 



Vallisneria, spiralis L. Tape grass. Wild celery. Ponds and slow 

 streams throughout. Common. 



GRAMINEAE. Grass Family 



Andropogon scoparius Michx. Broom beard grass. Dr} r open ground 

 or among pines. Frequent. 



Andropogon furcatus Muhl. Forked beard grass. Dry open ground. 

 Apparently infrequent. 



Digitaria humifusa Pers. Small crab grass. Sandy open ground in 

 and about Sault Ste. Marie. Plentiful. 



Digitaria sanguinalis (L.) Scop. Crab grass. Cultivated grounds 

 and about villages as a weed. Not abundant. 



Panicum capillars L. Old-witch grass. About cultivated grounds 

 and in villages as a weed. Apparently not abundant. 



Panicum depauperatum Muhl. Starved panic grass. On lumbered 

 over and burnt over sand ridges south of Vermilion. Apparently not 

 common. 



Panicum subvillosum Ashe. Spreading panic grass. Open sandy 



