APPENDIX. 497 



noticed have very narrow leaves, the former 6", the latter 4-5" wide. About St. George, Utah, a form 

 occurs with leaves only a" wide. 



5 2. HESPEEO-YUCCA. Filaments thickened upward, acute, smooth, mostly longer than the pistil, 

 erect ; anthers didymous, hroader than long ; ovary oval, the slender style tipped with a broad short 

 3-lobed stigma, bearing numerous filiform papilla; ; erect capsule looulicidally 3-valved from the 

 apex, valves entire, undivided ; seeds thin, smooth, with entire albumen. 

 4. Y. WiiippLEi, Torr. Bot. Mex. Bound. 222. Stems none or short, prostrate ; leaves few, often fal- 

 cate, rigid but not thick, gradually widening toward the broad base, rough on the margin, sharp-pointed 

 striated, glaucous, 12-18' long, i' wide or less; flowers panicled ; petals lance-oval, li-3' long ; capsule 

 small, ovate or obovate, obtuse ; seed narrowly margined .-From N. W. Arizona to the mountains and 

 coast ranges of S. California ; it may be expected in S. Utah. Flowers very different in size, some speci- 

 mens with the largest in the geuus ; style sometimes as long as the ovary or much shorter. 



The followiug genus is founded on a plant from W. Texas, originally described as a doubtful Tucca, 

 then as an Aloe, but evidently distinct from both. 



HESPERALOE, Eng. N. Gen. 



Perianth cylindric, of 6 (reddish) petal-like linear obtuse leaves, united at base, withering-persistent, 

 the outer ones cucullate at apex ; filaments from a broad adnate base, subulate-filiform, of the length of 

 the perianth, geniculate-inflexed below the tip ; anthers oblong, bifid below ; ovary ovate, 3-celled, 

 several times shorter than the filiform style ; small capitate stigma exsert ; caps»le.3-celled, 6-valvcd, with 

 6 rows of thin black horizontal Yucca-like seeds, with a linear diagonal embryo of the length of the 

 albumen.— Corm bearing the Yucca-like filamentose-margined leaves and a scape, with the fascicled flowers 

 in a spike or few-branched panicle. The leaves, pollen,' and seeds are those of a Tucca, the perigon and 

 pistil that of an Aloe; the filaments, being adnate at base and geniculate upwards, resemble those of an 

 Agave. 



HESPERALOE YUCC^FOLIA, Eng. ( Yucca (?) pamflom, Torr. Bot. Mex. Bound. 221. Aloe yucccefolia. 

 Gray. Proe. Aviei: Acad. 7. 390.) 



AGAVE, L. 



Perianth tubular, funuelform or carapanulate, persistent, 6-parted, the divisions nearly equal. 

 Stamens 6 ; filaments more or less adnate to the tube, inflexed in the bud, at last exsert ; anthers linear, 

 versatile. Pod coriaceous, 3-celled, looulicidally 3-valved from the apex. Seeds many, black, flat, hori- 

 zontal, in 2 rows in each cell. — Leaves thick and fleshy, mostly terminating iu a spine, on the margins 

 spiny-toothed or often cartilaginous-denticulate or rarely filamentous or entire, clustered at the base of 

 the many-flowered scape from a thick fibrous-rooted crown or on the top of a short trunk. 



A. Utahbnse, Engelm. N. sp. Leaves basal, stout, very fleshy, tapering from a broad base and 

 terminating in a long channeled spine, herbaceous on the sinuate margins between the horny flat teeth ; 

 scape bearing a dense spike of small yellowish flowers in fours or pairs ; the oblong obtuse erect lobes 

 of the perigon as long as the ovary, 3-4 times the length of the short campanulate tube ; stamens from 

 the middle of the tube, together with the style slightly exsert ; anthers of the length of the lobes ; capsule 

 cylindric-ovate, acute. — About St. George, Utah, (Dr. E. Palmer, J. E. Johnson.) Leaves at base 1^-2' 

 wide, 5' long, with stout broad white straight or rarely recurved spines on the margin ; terminal spine 

 whitish, nearly 1' long ; each leaf marked with the impressions of the teeth of those next to it ; scape 5-6° 

 high ; flowers, ovary included, about 1' long, tube very shallow, scarcely more than 1" long ; capsule and 

 seeds among the smallest in the genus, the former 9-10" long, the latter lJ-2" in longest diameter. 

 Allied with A. lieteracantha, Zucc, {A. PoselgeH, Salm. A. Leeliegmlla, Torr.,) which extends from Mexico 

 into New Mexico and Arizona. 



'The poUen-cells of Yucca are globose, 0.055-0.065 mm. diam.j those of Sesperaloe are similar but only 0.050-0.055 mm, 

 diam., and those of Aloe 0.030-0.050 mm. diam., globose when fresh, but when dry lanceolate, folded or grooved, (much lilse 

 those of Hyadntlms and many other lAliacece,) slowly becoming globose when soaked. 



63 



