THE SELAGINELLA RUPESTRIS GROUP. 151 



broader, with stronger teeth, and often stand at nearly 

 right angles to the stem, making the cone quite conspic- 

 uous. The cones are an inch or more long, and usually 

 there is but one fertile spike on each plant. The lowest 

 sporophylls bear three or four megaspores, which are as 

 large as the seeds of many flowering-plants. The fertile 

 spike is deciduous, but the sterile stems survive the 

 winter. 



Sclaginella spinosa is rare in the United States, being 

 found only in the elevated parts of Mairve, New Hamp- 

 shire, New York, Michigan, and Colorado. In British 

 America it is more abundant and found at lower alti- 

 tudes. It is also found in both Alaska and Greenland. 

 In the Old World it is reported from the British Isles 

 and across the northern part of the Continent, extending 

 south to Germany. It delights in moist, grassy places, 

 being much like the club-mosses in this respect. The 

 name of prickly mountain moss is in allusion to the 

 toothed leaves, though these are in no wise either spiny 

 or prickly. The specific name also alludes to this cir- 

 cumstance. In the days when this was thought to be a 

 club-moss it was called Lycopodium selaginelloides, or the 

 selaginella-like club-moss. Its transference to the genus 

 Sclaginella has made this specific name meaningless. 



