NEPHRODIUM. 



551 



111 his excellent work, " Ferns of ISTorth America," vol. i., p. 74, Eaton, referring 

 to this peculiar character, says that Mrs. Austin, to whom he is indebted for 

 a complete series of fine specimens of Ferns of Plumas County, California, is 

 the first person who noticed it. When writing to him on the subject, she 

 said : " I noticed this last fall when I went early (while it was yet cool) in 

 the morning for specimens for the press. I would not gather them as I did 

 not think they would make nice specimens, but went further up the creek, 

 collecting other plants, and did not return till two or three o'clock, when 

 I found the pinna3 all open and the fronds fit to press." Some subsequent 

 observations confirmed her in the opinion that this Fern at least has its daily 

 periods of contraction and expansion ; but whether the change is caused by 

 alternation of light and darkness, dampness and dryness, or heat and cold, is 

 yet undetermined. — Eaton, Fertis of North America^ i., t. 10. 



N. (Sagenia) nigrescens — Sag-e'-m-a ; nig-res'-cens (blackish). Baler. 



A stove species, of medium dimensions, native of Upper Gruinea, with 

 fronds IJffc. to 2ft. each way, deltoid (in shape of the Greek delta, A), 

 tripinnatifid (three times divided nearly to the midrib), and borne on grey 

 stalks 1ft. to 2ft. long. The leafy portion, of a parchment-like texture, is 

 nearly smooth and of a dark green colour. The moderately large and irregular 

 sori (spore masses) are disposed in series between the midrib and the edge of 

 the final lobes. — Hooker, Synopsis Filicum, p. 504. 



N. (Lastrea) noveboracense — Las'-tre-a ; nov-eb-or-ac-en'-se (native of 

 New York), Desvaux. 

 This interesting, greenhouse species, which in America is known under 

 the popular name of "New York Shield Fern," is found abundantly in moist 

 thickets and wet, grassy places in North America, principally from New 

 Brunswick and Canada to Virginia, also in Ohio, Kentucky, and North 

 Carohna. It is peculiarly distinct on account of the very slender character of 

 its undergromid- creeping rhizome (prostrate stem), which always keeps several 

 inches in advance of the developed fronds, and the youngest portion of which 

 is singularly downy. The spear-shaped fronds, Ift. to 2ft. long, 4in. to Gin. 

 broad, and borne on slender stalks about 1ft. long, are furnished with 

 spreadmg leaflets 2in. to Sin. long, cut down very nearly to the midrib into 



