THE OSMUNDAS. 27 



When full grown, the sterile fronds are often six feet 

 high with stipes a foot long, and spread out in circular 

 crowns like shuttlecocks or great green vases. They are 

 lanceolate or oblong-lanceolate in out- 

 line with twenty or more pairs of nearly 

 opposite, lanceolate pinnae cut nearly 

 to the rachis into numerous oblong, 

 rounded lobes. The fertile fronds are 

 totally unlike them ; in fact, in this 

 species the difference between the two 

 is probably greater than in any other 

 American fern excepting, perhaps, the 

 little curly grass. They are stiff, club 

 like and cinnamon-coloured and are A FRUITING PINNA. 

 very noticeable in the greening swamp- 

 lands of late spring. An examination of one of the woolly 

 pinnae composing these clubs will discover the counter- 

 parts of the ordinary green pinnae of the sterile frond 

 here reduced in area and covered with sporangia. 



The fertile fronds are at first bright green. About the 

 last week in May, just as they begin to assume the 

 familiar brown hue, the spores are shed in myriads, 

 the slightest touch sufficing to shake down a sage-green 

 cloud. At this stage a pinnule presents a beautiful sight 

 under a simple lens. The multitudes of tiny globes vary 

 in colour from the deep green of the unopened spheres to 

 the sulphur-yellow or rich brown of older empty ones. 

 Many will be found partly open, disclosing the spores 

 within. Most species have brownish spores, but those of 

 the Osmundas are of a beautiful shade of green, due to 

 the amount of chlorophyll they contain. Perhaps because 

 of this rather perishable chlorophyll, they must germinate 

 within a few days after they are shed or they will be 



