Nelson — Th-c Genus Psilostrophe. 21 



avia are often something else. As observed by Dr. Gray, the foliage is 

 not essentially different from P. tagetina. One might suspect that some 

 distributors believe the specific name refers to the pubescence of the 

 leaves. It seems to be confined to Texas and adjacent Mexico. 



Chas. Wright, No. 380, Western Texas, 1849; C. G. Pringle, No. 9040, 

 Jaral, Mexico, 1900; F. S. and E. S. Earle, No. 446, Devil River, Texas, 

 1900; Mex. Bound. Surv., No. 628; L. H. Dewey, College Station, Texas, 

 1891; V. Havard, No. 45, Stockton, Texas, 1881; M. E. Jones, No. 3718, 

 El Paso, Texas, 1884. 



3. Psilostrophe cerifera, n. sp.* 



Stems few to several from the enlarged crown of a ligneous taproot, 

 or more rarely the crown raised on a short simple caudex; the stems 

 simple or sparingly branched, 1-2 dm. long, floccose-tomentose; leaves 

 lightly lanate. entire, lanceolate-spatulate, obtuse or acute at apex, the 

 tapering base scarcely petioled; inflorescence corymbose, the rather 

 small heads congested on the tips of the branches of the corymb; bracts 

 of the narrow involucre broadly linear, in one series, rigid and closely 

 connivent, the waxy or resinous particles with which they are sprinkled 

 obscured by the lanate pubescence but extending to all parts of the 

 flowers, the akenes, and even to the leaves of the plant; rays usually 3, 

 the ligule 3-4 mm. long and nearly twice as broad, its slender tube 

 equalling the ligule and almost equalled by the linear pappus-scales; 

 disk flowers 10 or fewer, slightly articulately enlarged at the summit of 

 the tube proper; akenes glabrous, not striate, somewhat 4-angled; pap- 

 pus linear, nearly as long as the disk corollas. 



The type is Mr. M. A. Carleton's No. 201 (in Ry. Mt. Herb.), from the 

 Cheyenne Country, Indian Territory, June 1891; distributed by the U. 

 S. National Herbarium. Wholly typical are Mr. Paul J. White's speci- 

 mens, Woods County, Oklahoma, June 29, 1900. Mr. Hitchcock's No. 

 741, from the Gypsum hills of Barker County, Kansas, is undoubtedly 

 the same, though, on account of age, the leaves are largely wanting. A 

 specimen by Prof. Kellerman, from Kansas, 1888, is more floccose woolly 

 and has the appearance of being merely biennial, and this may be true 

 of Mr. Hitchcock's specimens (the number cited) also. 



A very abnormal form is found in Mr. B. B. Smyth's specimens, No. 

 140, from Crooked Creek, Meade County, Kansas, which tends to con- 

 firm the suspicion that in more northern localities this species is alto- 

 gether biennial. These may be designated: 



3a. Psilostrophe cerifera biennis, n. var. 



Larger than the species, mostly single-stemmed from the crown, often 

 freely and intricately branched above, densely and permanently floccose 



*A paratype of Psilostrophe cerifera A. Nelson is in the National Herb- 

 rium under the herbarium number 20,577. 



