404 USEFUL PLANTS OF GUAM. 



olate, acuminate, produced below into an acuminate appendage, rachia of the 

 leaflets 8 to 12 mm. long, leaflets very shortly stalked, linear-lanceolate or lance- 

 olate, acute, often unequal-sided, glabrous, rigid, dotted with black glands beneath; 

 bracts inclosing the flowers ovate, acute, reticulate-veined, leaf-like, persistent, 

 often ciliate, dotted like the leaves, arranged in stiff, erect, very lax axillary spikes; 

 flowers with minute calyx having the upper segments connate, the petals exserted, 

 and the stamens monadelphous; pod jointed, easily separable into flattened, inde- 

 hiscent 1-seeded joints, either quite inclosed between the bracts or slightly exceed- 

 ing them; surface of the joints set with numerous short, straight spines. 

 A common weed growing in waste places and on the sites of abandoned clearings. 

 Ebfeeences: 

 Zomia diphylla (L.) Pers. Syn. 2: 318. 1807. 

 Hedysarum diphyllum L. Sp. PL 2 : 747. 1753. 

 Zostera tridentata Solms. Same as Halodule uninervis. 



Zygomenes cristata. Chested spiderwoht. 



Family Commelinaceae. 

 A common weed growing in open places, with 3-petaled flowers in terminal scor- 

 pioid, bracteate cymes, inclosed in large falcate, imbricating, 2-seriate bracteoles. 

 Stem creeping below, branches ascending; leaves ovate-oblong, subacute; the petals 

 and stamens alone are exserted beyond the bracteoles; sepals 3; corolla with a 

 funnel-shaped tube and a spreading, equally 3-lobed limb; stamens 6, bearded; 

 ovary 3-celled; cells usually 2-seeded; style thickened at tip; seeds striate and pitted. 

 A plant widely spread in the Tropics. 

 References: 

 Zygomenes cristaicHVL. ) 

 Commelina crisiata L. Sp. PI. 1 : 42. 1753. 

 Cyanolis cristata (L.) D. Don, Prod. Fl. Nep. 46. 1825. 

 Tradescanlia cristata L. Syst. ed. 12. 233. 1767. 

 Salisbury's name, Zygomenes is thirteen years earlier than Don's publication of 

 Cyanotis. 



