Lyon: the pteridopiiytes of Minnesota. 249 



Botrychium obliquum Muiil. ; Willd. Sp. PL 5: 63. 1810. 



Infrequent in damp woods and meadows throughout. 



Herb.: Taylor, Chisago lake; Sandberg, Sandy lake; 

 Campbell, Ottertail Co.; Wheeler, Lyon, Echo lake; Lyon, 

 Ft. Snelling reservation ; Rosendahl, Spring Grove ; Mac- 

 Millan, Brand and Lyon, Grand Marais ; MacMillan and 

 Sheldon, Lake of the Woods ; Wheeler, Rosendahl, Butters 

 and Lyon, Lake Itasca. 



The specimens cited above present a most perplexing array 

 of forms. A further field-study and comparison with authentic 

 specimens must, however, be made before they can be assigned 

 to other than this species. 



During the spring of the present year, gametophytes of this 

 plant have been collected in considerable numbers by the writer, 

 near Echo lake. In shape they resemble those of Botrychium 

 virginianum but are only about one third their size. The 

 reproductive organs are produced on the upper side. The 

 primary root of the embryo sporophyte grows down through 

 the tissue of the gametophyte instead of coming out on the 

 upper side as in B. virginianum. 



The root often protrudes an inch from the prothallium before 

 the first leaf bursts through the calyptra. The life-history of 

 the plant will be worked out as far as possible from the material 

 obtainable. 



Botrychium virginianum (L.) Swz. Schrad. Journ. Bot. 2 : in. 

 1800. Rattlesnake-fern. 

 Throughout the state. 

 Herb. : Many specimens. 



The gametophytes of B. virginianum have been collected jn 

 two localities in this state. Lyon, Grand Marais, 1901 ; Lyon, 

 Echo lake, 1903. 



Family OSMUNDACE^. 



Osmunda regalis L. Sp. PI. 1065. 1753. Royal fern. Flow- 

 ering fern. 



Frequent throughout the northern half of the state. Low 

 open woods. 



Herb. : Numerous collections. 



Osmunda claytoniana L. Sp. PI. 1066. 1753. Interrupted 



fern. 

 Throughout the state. In moist shaded soil. 

 Herb. : Many specimens. 



