48 RATTLESNAKE FERN AND ADDER'S-TONGUE. 



In America the adder's-tongue is found from Canada 

 to Florida, Missouri and sparingly to California. In the 

 Old World it occurs in Europe, Asia, Africa and Aus- 

 tralia. Considering its wide distribution, some difference 

 in specimens from remote points may be expected. In 

 the western part of our range, there is a form named 

 Engelmanni. It may be distinguished from the type by 

 the slender stipe and apiculate sterile portion with 

 broad areolae and anastomosing veins. It is found as 

 far east as Virginia. This also is probably a form of 

 vulgatum and better characterised as O. vulgatum Engel- 

 manni. 



The common name of adder's-tongue is much older 

 than the scientific Ophioglossum and both have the same 

 meaning. Adder' s-spear, adder's-spit and other names 

 formerly in use, all refer to a fancied resemblance be- 

 tween the plant and the adder. The fronds were long 

 used as the principal ingredient in " adder' s-spear oint- 

 ment " to make which they were boiled with unsalted 

 butter. Drayton alludes to its use in the lines 



" For them that are with newts, or snakes or adders stung 

 He seeketh out a herb that's called adder's-tongue, 

 As Nature it ordained its own like hurts to cure, 

 And sportive, did herself to niceties inure." 



There are about twenty species of Ophioglossum known. 

 In northeastern America, there is but a single species 

 unless the two forms noted should prove distinct. Three 

 other species are sometimes found in tropical parts of 

 the United States. 



