CHAPTER XVIII 



NARROW-LEAVED CHAIN-FERN 



Lorinseria areolata. 



Rootstock wide-creeping, forking, dark brown, at least when 

 dried, furnished with light brown, concolorous, ovate, acute, 

 entire scales: leaves scattered, distant or approximate, borne on 

 all sides of rootstock; roots springing from rootstock, equalling 

 or slightly exceeding the petioles in number. 



Leaves dimorphous, somewhat sensitive to frost; sporophylls 

 erect, twelve to twenty-eight inches long; sterile leaves shorter. 



Petioles compressed at base, somewhat chaffy, bordered on 

 each side for some distance from apex downward by a fine ridge: 

 in sterile leaves longer to shorter than blades, slender, chestnut- 

 brown below, often furrowed on face and sides, at least when 

 dried, the lateral furrows containing the lateral ridges: in sporo- 

 phylls stouter, elongate, rigid, light chestnut-brown to purplish- 

 ebony, subterete: scales hyaline, ovate, acuminate, entire or 

 subciliate, thinly clothing base of petiole, upper scales few and 

 scattered or absent: fibrovascular bundle solitary, arched at 

 back, more or less channelled on face. 



Blades of sterile leaves ovate-deltoid, below pinnate or sub- 

 pinnate, above parted, gradually or abruptly narrowing to the 

 often sinuate or sinuately lobed base of the ovate-lanceolate or 



