Maxon — Lip-ferns Related to Cheilanthes myriophylla. 147 



especially, the filamentous tips of the reduced under ones are more or less 

 intricately recurved among the segments and reach the upper surface of 

 the pinnae, there freely overlying the ultimate rachises and segments — a 

 condition which scarcely exists in C. Fendleri from the paucity of reduced 

 scales and the absence of cilia upon the large ones. In general cell struc- 

 ture the scales of the two species are similar, but the characters above 

 mentioned, together with the characteristic scanty aspect of C. Fendleri, 

 with its more richly colored, concave scales, are unmistakable. The 

 occasional occurrence together of these two closely related species is com- 

 parable to the case of Pellaea Wrightiana and P. longimucronata , recently 

 discussed,* and is not in itself remarkable. Differences in scale structure, 

 if fixed, are the very characters upon which dependence is to be placed, 

 in xerophilous fern genera such as Cheilanthes, and there is in the present 

 instance no indication whatever of intergradation. 



The following additional specimens of Cheilanthes Wootoni are in the 

 National Herbarium. 



Akizona: North slopes of Huachuca Mountains, July-Oct., 1882, Lem- 

 mon, in part; Santa Rita Mountains, May 27, 1881, Pringle; Coronado 

 Mountains, alt. 1950 meters, Goldman 2370; Lower Soldier Canyon, 

 Santa Catalina Mountains, alt. 1320 meters, Shreve 5117; Santa Catalina 

 Mountains, March, 1881, G. R. Vasey, in small part; head of Rincon 

 Valley, Rincon Mountains, Blumer 3291; Nogales, W. Palmer 1202; 

 Bowie, Jones 426S; Lowell, W. F. Parish 275; Clear Creek, MacDougal 

 629; without locality, E. Palmer. 



New Mexico: Organ Mountains, Dona Ana County, alt. 1650-1800 

 meters, May 20, 1893, Aug. 6, 1895, and Nov., 1905, Wooton, the two first 

 in part; same locality, July 7, 1897, Wooton 104, in part; same locality, 

 June 9, 1906, Standley; Santa Fe, Rothrock 52; Burro Mountains, Rusby 

 I, in small part; same locality, Rusby H 1, in greater part; without 

 locality, Wright 2126, in part. 



5. Cheilanthes Covillei Maxon, sp. nov. 

 Rhizome short-creeping and freely branched, the very numerous short 

 divisions usually close and intricate, 2-4 mm. in diameter, very densely 

 paleaceous, the scales appressed, closely imbricate, linear to lanceolate, 

 long-attenuate, 1.5-2.5 mm. long, 0.2-0.5 mm. broad, straight, more or 

 less denticulate-serrulate at the tip, dark brown or blackish, rigid, 

 strongly sclerotic and opaque throughout, except for the extremely nar- 

 row, delicate, pale border. Fronds numerous, erect, closely distichous, 

 10-30 cm. long; stipe slender to stoutish (0.6-1.3 mm. in diameter), 

 5-17 cm. long, straight or subflexuous from an arcuate base, brown to 

 dark purplish, sublustrous, thinly and deciduously paleaceous, the scales 

 small, pale, linear-attenuate, laxly ascending; lamina oblong to ovate- 

 deltoid or deltoid, acuminate, 5-14 cm. long, 2-6 cm. broad at or near the 

 base, tripinnate, the larger tertiary segments ternately to pinnately divided, 

 the divisions commonly unequal; rachis similar to the stipe, but more 

 densely paleaceous; larger pinnae 8-12 pairs, mostly contiguous or 

 * Proc. Biol.Soc. Washington, 30 : 179-184. 1917. 



