436 TRELEASE— THE DESERT GROUP XOLIXE.^. [April 21, 



Barbae Cilia gracilis Brongniart, /. c. — As synonym. 



Yucca gracilis Otto, Allgem. Gartenzeit. 9: 123. 1841. — As 



synonym. 

 Bonapartca gracilis Otto, /. c. — As synonym. 

 Dasylirion gracilc Znccarini, Abhandl. Akad. Miinchen. CI. II. 4 



(=:Denkschr. 19): 22. 1845. 

 Dasyliriuui acrotrichuin Kunth, Enum. PI. 5 : 40. 1850. — Hooker, 



Bot. Alag. iii. 14. pi. 30_^o. — Copied in Fl. des Serres. 14. pi. 



1448. — Schlotthauber, Deutsch. Mag. f. Gart.-u. Blumen- 



kunde. 1871 : 49, 64, 81, 96. 2 pi. — Koopmann, Gartenwelt. 3 : 



375-6. /. 

 Dasyliriuui gracilc Planchon, Fl. des Serres. 7: 6, 10. /. 1851-2. 

 Littcca gracilis \^erschaffelt, Cat. 1864. — Hansgirg, Phyllobiol- 



ogie. 422. 

 Dasylirion acrotriclnmi Baker, Journ. Bot. 10: 297. 1872. — 

 Kegel, Gartenflora. 30: 24. /.— Gard. Chron. iii. 19: 204. pi. 

 — Deutsch. Gartner-Zeit. 20 : 536. /. 

 ?P. rohustum Hort. — {Y'er\\2.^s,^scrratifolium.) 

 Caulescent. Trunk at length i m. or more high. Leaves 6-10 

 or rarely 15 mm. wide, less than i m. long, green 

 and glossy or somewhat glaucous and dull, often 

 rough on the keels: prickles 5-10 or 15 mm. apart, 

 scarcely 2 mm. long, rather straight, pale yellowish, 

 with slightly brown tips. Inflorescence 3-5 m. or 

 more high. Perianth segments 2-3 mm. long. Fruit round-cordate, 

 6-7 X 8-9 mm., the thick style about equaling the shallow notch. 

 Seed 3 X 3-5 mm.— P/. //, 12. 



East-central Mexico. Collected by Schiede and Deppe on the 

 Serro de la Ventana, on the flanks of Mt. Orizaba, by Karwinski at 

 Ixmiquilpan, and by Reppert at Real del ]Monte. Deppe's original 

 seed collection, in 1825 (Otto, Allgem. Gartenzeit, 16: 276. 1848) 

 was made between Real del ^lonte and Pachuca, and most of the 

 earlier plants of European gardens were raised from this at Berlin 

 (Bouche, Monatsschr. Verein Beford. Gartenbau. 1880: 481). — 

 Range of the preceding. 



Specimens examined: Hidalgo. Dublan (Priiiglc, iiig6, 1902; 



