32 Trans. Acad. Sci. of St. Louis. 



belong to this section of the genus. Notwithstanding the 

 absence of adequate flowering material, enough fragments 

 and remnants have been seen to warrant the belief that in 

 floral characters they are somewhat intermediate between 

 the Sisalanae and Tequilanae, more closely approaching 

 the latter. Though the wild species seem to fruit freely, 

 capsules appear to be rare on the cultivated forms, and, 

 as with A. sisalana, statements that they never fruit are 

 to be found. All appear to be freely bulbiferous after 

 flowering, and thus to afford "pole plants" as well as 

 offsets, by which they are propagated, being permanently 

 set at about six-foot intervals after a preliminary stay in 

 closer nursery plantation. 



End spine acuminately tapering, triquetrously subterete, not grooved, con- 

 vex to barely a little concave at base, polished, at length blackish 

 chestnut: marginal prickles rather slender, gradually tapering or with 

 abruptly widened or sublenticular bases: leaves glaucous. A. Zapupe. 

 End spine broadly triquetrous or nearly half round, obliquely flattened or 

 broad-grooved to beyond the middle, sometimes with raised edges, or 

 round-grooved on young leaves, polished, often turning gray. 

 Spine and prickles blackish: spine gradually tapering: prickles rather 

 slender, gradually tapering; leaves gray-green. A. rubescens.* 



Spine and prickles red or brown: spine somewhat acuminately taper- 

 ing: leaves green. 

 Prickles small and slender, from lenticular bases. A. Lespinassei, 



Prickles heavy, deltoid below or tapering from wide bases. 



A. Endlichiana. 



End spine gradually tapering, nearly terete, round-grooved often to or 



beyond the middle, rather dull below, reddish or rarely purplish brown, 



often turning gray. 



Prickles heavy, from deltoid bases: leaves grayish. A. aboriginum. 



Prickles rather slender, gradually tapering or from lenticular bases: leaves 



green. A. Deiveyana. 



Agave Zapiipe n sp. 



Leaves ratlier dark green, persistently glaucous, striate, thin, gradually 

 acute, 8-lOX ir)0-2()0 cm.: end spine from bright red-brown becoming 

 nearly black, smooth and glossy, gently curved, obtusely a little triquetrous, 

 acuminately and subacicularly pointed from a broad convex flattened or 

 slightly concave base, somewhat produced ventrally into the green tissue, 

 4X15-25 mm., not decurrent: marginal prickles similarly colored, usually 

 15-30 mm. apart in the middle, reduced or wanting near the tip, 2-3 mm. 

 long, slender, straight or mostly upcurved, gradually tapering or their bases 



* See Rept. Mo. Bot. Gard. 18 : 254. pi. 31-34. (1907). 



