Ophioglossum Ophioglossaceae 37 



PTERIDOPHYTA. Ferns and Fern Allies 



Note: Ferns and their allies have always been an attractive subject of 

 study and many persons have made intensive studies of them and have 

 designated many of the minute differences by special names. No attempt 

 has been made here to evaluate the status of these variations and the com- 

 mon interpretation of them has been accepted. 



In this treatment the term frond is used to mean the expanded portion of 

 the leaf of a fern. 



[Students who wish to use the stipe to assist in the determination of the 

 ferns are referred to "An analytical key for the ferns of the Northeastern 

 States, based on the stipes," by C. E. Waters, published in 1903 and re- 

 published as a supplement to the American Fern Journal, vol. 18: no. 

 2. 1928.] 



1. OPHIOGLOSSACEAE Presl Adder's Tongue Family* 



Sporangia cohering in a simple spike; fronds (leaves) one, rarely 2 or 3, entire; 



veins reticulate 1. Ophioglossum, p. 37. 



Sporangia in pinnate or compound spikes, rarely in a simple spike but not cohering; 



fronds (leaves) not simple; veins free 2. Botrychium, p. 38. 



1. OPHIOGLOSSUM [Tourn.] L. Adder's Tongue 



Fronds mostly rounded or obtuse at the apex, rarely acute but never apiculate 



1.0. vulgatum. 



Fronds more or less acute at the apex and apiculate 2. 0. Engelmanni. 



1. Ophioglossum vulgatum L.** Common Adder's Tongue. Map 1. 

 Local in various habitats in the southern half of the state. It is always found 

 in dense shade and most commonly associated with beech, especially in low 

 beech and sweet gum woods. Ordinarily it seems to prefer a slightly acid 

 soil. It has been found in Lake County by several collectors, where it is 

 evidently rather frequent. I have a specimen collected by Edwin D. Hull 

 near Liverpool, Lake County, which was growing under some shrubs in 

 almost pure sand with cranberry. Mr. Hull found more than 30 fruiting 

 specimens at this time at the place mentioned above. Besides the counties 

 shown on the map it has been reported from Crawford, Harrison, and 

 Wayne Counties. 



Markle (Proc. Indiana Acad. Sci. 1915: 357. 1916) in 1914 found near 

 Gary, Lake County, many plants with more than one leaf. He reports "of 

 a total of two hundred plants, selected at random, ninety-one had one leaf 

 above ground, one hundred and five had two leaves, and four had three 

 leaves". 



la. Ophioglossum vulgatum f. pseudopodum Blake. (Rhodora 15: 87. 

 1913.) This is a form in which the sterile blade is narrowed below into a 

 stalklike base a fourth to two thirds as long as the expanded portion. This 

 form has been found in St. Joseph County by R. M. Tryon, Jr. 



P. E. I., Ont. to Alaska, south w. to Fla. and Mex. ; also in Eurasia. 



* R. T. Clausen checked the determination of all my specimens and rendered 

 valuable help. 



** For a discussion of this species and varieties see Rhodora 41:494-499. 1939. 



