RARE FORMS OF FERNS.— I. 



A ROUND-LEAVED ROYAL FERN. 



We illustrate, herewith, a curious form of the royal 

 fern {Osmunda regalis) from Hartland, Vt., collected 

 by Harold G. Rugg. The figure shows the two middle 

 pairs of pinnae and a part of what appears to be the 

 normal fruiting apex. Specimens are at hand, however, 

 in which the apex of the frond is leafy and the sori 

 borne on reduced pinnae lower 

 down. An examination of these 

 latter, however, discovers that they 

 are but incompletely fertile, most 

 of the sori being scattered along 

 the margins of leaf-like expansions. 

 Because of this latter characteristic, 

 some fern students, who have seen 

 the specimens are inclined to call 

 the species Osmunda Claytoniana, 

 and others have suggested a hybrid 

 between this and O. regalis. The 

 veining and texture of the pinnules 

 is so evidently that of O. regalis, 

 however, that the aberrant fruiting 

 may be disregarded, since it is not 

 uncommon for abnormal fronds of 

 any of the Osmundas to deviate 

 from the usual in this respect. In 

 the present specimens it is inter- 

 esting to note that the imperfectly 

 fertile pinnae have veins tipped with 

 spore-cases that spring from the surface of the pinnae 

 instead of from the edges. 



The fern illustrated has been growing on the farm of 

 B. P. Ruggles for the past twenty years and therefore 

 seems worthy of a name to designate it. I would ac- 

 cordingly call it Osmunda regalis f. orbiculata. It may 

 be described as follows : Rootstock as in the type ; 



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