usually 5 or rarely 7, broadly oval, coarsely toothed, to about 2 cm. long, cuneate 

 at base, light-green, glabrous above, finely puberulent and more or less granuli- 

 ferous beneath; flowers mostly 2 or more, sometimes solitary; pedicels glabrous, 

 about 1 cm. long; hypanthium globose, glabrous, in fruit 7-8 mm. broad; sepals 

 broadly lanceolate, caudate-attenuate, 1-1.5 cm. long, tomentose on the margins, 

 glabrate dorsally; petals obovate, dark-rose-colored, to 2 cm. long; styles distinct, 

 persistent, not exserted. 



Wet meadows and seepage banks along streams in N. M. (Valencia Co.) and 

 Ariz. (Apache, Navajo and Coconino cos., s. to Cochise and Pima cos.), May- 

 July. 



Fam. 74. Leguminosae Juss. Legume Family 



Trees, shrubs, vines or herbs; leaves and branches alternate; stipules usually 

 well-developed and persistent; leaves usually compound (when simple then so 

 through reduction or fusion), the leaflets often with stipels; flowers rarely solitary, 

 usually in terminal or axillary panicles, racemes, spikes, heads or glomerules, 

 usually perfect and complete, perigynous (but the floral cup sometimes evanes- 

 cently short and the flowers essentially hypogynous), bilaterally symmetrical (in 

 the Mimosoideae. appearing radially symmetrical except for the gynoecium) and 

 often markedly zygomorphic (especially in the Papilionoideae) ; calyx valvate at 

 a very early stage of development or variously imbricate; sepals 5, these in most 

 genera fused at least partly and in some genera only 4 in number through fusion; 

 corolla basically of 5 petals attached at the rim of the floral cup, rarely fewer 

 through reduction (and in the Papilionoideae, often appearing to be only 4 be- 

 cause of fusion of the lower 2), in some genera of the Mimosa group the petals 

 neotenically connate; aestivation valvate or variously imbricate; stamens 1 to 

 numerous, separate or variously coalescent in groups or in some flowers of some 

 genera modified into staminodia; gynoecium of a single superior simple pistil 

 with a ventral placentary suture oriented upward in most flowers, the ovules 1 

 to numerous and attached in 2 alternating rows to the coalescent margins of the 

 placentary suture; style simple; fruit a "pod" or follicle-like usually dry structure, 

 either indehiscent or breaking up into 1 -seeded sealed units or most commonly 

 splitting lengthwise both along the ventral suture and the dorsal "midrib" (when 

 thus dehiscent the fruit is said to be a "legume"); seeds 1 to numerous, with 2 

 thin integuments, essentially none or very little endosperm and large well-de- 

 veloped embryos. Fabaceae; Papilionaceae; Mimosaceae. 



The Leguminosae comprise over 500 genera and well over 10,000 species and 

 are distributed in all parts of the world inhabitable by seed plants. They include 

 some of the extremely important economic plants such as beans, peas, alfalfa 

 and clovers. 



This family posed one of the most difficult problems in regard to what plants 

 should or should not be included. For instance, perhaps more of the clovers 

 should have been included, but time limitation prevented us from pursuing this 

 further. Several woody species, namely, our huisache {Acacia Smallii Isely) and 

 retama (Parkinsonia aculeata L.) occasionally cover low, poorly drained or even 

 flooded areas, and sometimes they completely fill up tanks and ponds to the 

 point of causing complete desiccation of these habitats. Perhaps these should 

 have been included. 



1. Leaves simple, linear to linear-oblanceolate 16. Alhagi 



1. Leaves compound, with 2 or more leaflets (2) 



2(1). Leaves (at least some) pinnately twice-compound (3) 



2. Leaves pinnately once-compound or pinnate (6) 



1039 



