1648 CXXXVIII. XYKIDEiE. [A-yris. 



Placentas of the ovary parietal, free from each other and extending to the 

 apex of the cavity. 

 Bracts entire or minutely ciliate. Anther-cells dorsally affixed to a small 

 connective. Staminodia jletiicillate. 

 Leaf-tufts on a perennial stock, with rigid sheathing bases. Staminodia 



densely penicillate • 1. X. complanata- 



Leaf-tufts annual. Leaves grass-like. Staminodia very slender, with 



few hairs or scarcely any . 2. A", paiiciflora. 



Placentas very short and confluent at the base of the ovary. _ . , 



Other characters of A'. o^^cj-ciiZffte, but bracteoles not winged . . _. . S. X. gracilis. 

 Placentas connate at the base of the ovary, extending also up the sides. 

 Capsule usually hardened at the apex. 

 Staminodia densely penicillate. Bracteoles with a prominent or winged 

 usually ciliate keel. ' 



Bracts broad, glabrous, appressed, entire or theinner one jagged . . 4. A. operculala. 



1. X. complanata (flattened), 11. Bi. Prod. 2.5G ; Bmith. Fl. Austr. vii. 77. 

 Stock perennial. Leaves tufted, generally surrounded by a few old brown sheaths, 

 grass- like, flat, often very narrow, varying from 1 or 2 to above Sin. long. Scape- 

 more or less flattened, from under 1ft. to about l|-ft. high. Flower-head at first 

 short and ovoid, but sometimes lengthening into a cylindrical spike of ^ i>o lin.^ 

 the scales broad, light-brown, entire or the inner ones slightly ciliate, the lower 

 empty ones very few. Bracteoles prominently keeled or with a narrow dorsal 

 shortly ciliate wing. Inner perianth-segments broad but small. Anther-cells, 

 quite distinct, dorsally attached to a small connective ; staminodia densely 

 penicillate. Style divided nearly to the base. Placentas of the ovary free from 

 each other and extending to the apex of the cavity. Seeds very numerous and 

 small. — A', lavis and X. scahra, E. Br. Prod. 256 ; X elonr/ata, Eudge in Trans. 

 Linn. Soo. x. 289, t. 15 ; F. v. M. Fragm. viii. 205. 



Hab.: Islands of the Gulf of Carpentaria, JR. Brown; racing Island (X.lmvis), JR. Brown;. 

 Moreton Bay, F. v. Mueller and others; Eockhampton, O'Shanesy ; Endeavour iUver, A. 

 Cwminyliam ; Rockingham Bay, Ballacliy ; Port Denison, Fitzalan. 



The species is also in East India if A. Walkeri, Wight in Kunth, Enum. iv. 19, be really 

 identical, as it appears to be. 



Var. bracteata. Outer scales of the flower-head enlarged into spreading I racts of 3 to 4 

 lines. 



Hab.: Moreton Bay, Leichhardt. 



Var.? lep'.ocaidis. Scapes very narrow, scarcely compressed or angular-terete. Flower- 

 heads small and short. Flowers not examined. 



Hab.: Cape York, M'Gillivray ; Upper Brisbane Eiver and Providence Hill, F. v. MuelUr. 



2. X. pauciflora (few-flowered), Willd. Phytogr. i. 2, t. 1 ; Benth. Fl. Austr^ 

 vii. 77. Apparently annual. Leaves in radical tufts, grass-like, narrow, rarely 

 above 6in. long. Scapes sometimes only 2 or Sin. high, but varying from that 

 to 1ft. or rather more, terete or slightly flattened. Flower-head ovoid-globose, 

 attaining 4 to 5 lines diameter when full-grown but often very much smaller, the 

 scales very broad, entire, brown with very thin almost hyaline margins. 

 Bracteoles- thin and light-coloured, quite glabrous without prominent keels. 

 Perianth small for the genus. Anthers almost sessile, the cells quite distinct 

 dorsally attached to a small connective ; staminodia very slender, with very few 

 terminal hairs and often very difiicult to find. Capsule obovoid, the placentas- 

 adnate to the apex of the valves. — Kunth, Enum. iv. 17 ; X. ■paucifl.ora,. 

 X. paludusa, X. dentindata, and X. jnisilla, E. Br. Prod. 256 ; X. oligantha, 

 Steud. Syn. Glum. ii. 288. 



Hab.: Endeavour Eiver, Baij/cs ajicZ Sotoider, A. Cunningham; between Norman and Gilbert 

 Elvers, T. Gulliver. 



The species is also widely spread over tropical Asia. Brown's four species were all described 

 from Banks and Solander's Endeavour Eiver specimens, and appear to me to differ only in size 

 and luxuriance ; the two smallest slender forms, 2 to 3in. high with very small heads (X. 

 pahidosa anflpusilla), gathered in tbe same locality by Cunningham, represent well Willdenow's 

 figure ; the larger forms are, however, more frequent in India as well as in Australiaa 

 collections. — Benth. 



