The Tamaricaceae in the southeastern United States

only on abaxial surface in Myricaria gennanica]. Inflorescences spicate or racemiform, often aggregated in terminal panicles [or flowers solitary in Hololachna and Reaumwia]. Flowers perfect [2 species of Tamarix dioecious], regular, small, hypogynous, 4-or 5-[6-]merous; pedicels subtended by small, scalelike bracts. Sepals 4 or 5 [6], free or slightly connate, persistent, imbricate. Petals 4 or 5 [6], alternating with and larger than sepals, free, sometimes persistent [with a pair of ligular appendages near base in Reaumuria], inserted at base of a fleshy or membranaceous disc, imbricate. Stamens 4 or 5 [to 10 in Tamarix, to 75 in Reaumuria], usually haplostemonous or obdiplostemonous, usually free [monadelphous in Myricaria, fasciculate in 5 bundles in Reaumuria]; filaments filiform; anthers tetrasporangiate, 2-locular, versatile, extrorse in Tamarix [introrse in Myricaria], longitudinally dehiscent, slightly longer than wide; pollen (2-) 3-(4-)colpate, simple or in tetrads, binucleate (in Tamarix) [trinucleate in Myricaria]. Gynoecium or(2) 3 or 4 ( Fruit a loculicidal, pyramidal capsule, the 3[-5] valves placcntifcrous at base, coriaceous; seeds long-pilose over entire surface [Reaumurieae] or at apex only, with unicellular hairs, which may be prolonged into a conspicuous hygroscopic coma (Tamariccae), micropyle formed by endostome; endosperm with development nuclear [cellular in Tamarix tctrandra], degenerating quickly in Tamariccae [persistent in Reaumurieae]; cotyledons 2, oblong, obtuse at apex, flat or plano-convex, the radicle short, conical, inferior; megagametophyte (embryo sac) tetrasporic, but postmeiotic development variable, usually Fritillaria or Adoxa type, embryogenesis of Solanad type, with broad, massive suspensor formed, polyembryony occasional. Base chromosome number 12. (Including ReaumuriaceaeEhrenberg.) Type genus: Tamarix A relatively small family of five genera {Hololachna Ehrenb., Myricaria Desv., Myrtama Ovcz. & Kinz., Reaumuria L., and TamarixL.) and about 100 species, occurring primarily in central Asia, the Middle East, northern Africa, and the Mediterranean region of Europe. Several species of Tamarix have been introduced into North America, and six of these have become naturalized in the Southeast.'