KE VISION OF THE GENUS NAJAS. 421 



to 4 mm. broad, with 10 to 17 marginal teeth, which are relatively large triangular out- 

 growths capped with a sharply-pointed spine-cell, and often equal in length to the leaf- 

 width ; there are no hypodermal strengthening fibres. Sheaths 3 '3 to 3*5 mm. long ; 

 auricles about J the length of the whole, with 3 to 5 suberect ii^eWi on the narrow ajiex 

 and outer margin, and sometimes continued for a short distance down the sheath-margin. 

 Male flowers 3 mm. long ; the narrow neck of the spathe ends in a few long sharp spines ; 

 the two lips of the perianth are large and conspicuous. Female flowers 3*25 mm. long, 

 the slender style dividing into tw^o long narrow-linear stigmas. Fimit absent. 



Australia — {Leichhardt). 



Very near Ncijas tenuifolia, but, so far as it is possible to judge from the very scanty 

 material, distinguished by its more prominent leaf-teeth, and the longer neck of the male 

 spathe. 



27. Najas AUSTiiALis, Bory. (PI. XLII. ligs. 172-176.) 

 iV. australis, Bory ex Cham, in Linnaea, iv. (1829) 501. 

 N. minor var. indica, A. Br. in Journ. Bot. ii. (1864) 278, in part. 

 Caulinia alternifolia, Willd. ex Cham. /. c. 



Planta laxissima, ramis tenuibus elongatis, internodiis sagpe tiliformibus ; foliis lomris 

 anguste linearibus, superne angustatis et subsetaceis, ascendentibus, debilibus, in 

 siccis flexuosis, nervo mediano cum lineis horizontalibus in foliis validioribus 

 conspicuis, dentibus marginalibus breviter triangnlis, superne magis prominentibus ; 

 vaginis ssepe cylindricis, superne late rotundatis et dentibus minutis numerosis 

 instructis ; squamulis intravaginalibus anguste linearibus obtusis ; florihus masculis 



; femineis brevibus vagina inclusis ; ovario nudo ellipsoideo, stylo brevi in 



stigmata duo diviso ; fructu anguste ellipsoideo, pericarpio semen rugulosum arete 

 includente ; testa areolis minutis quadratis regulariter notata. 

 A very lax plant, with a grass-like, more or less strict habit, or sometimes diffuse. 

 Shoots long and slender, reaching 50 cm., and probably more ; lower internodes 3 to 8 

 cm. long, "75 to I'S mm. broad, becoming much shorter above, lo to 1 cm., and scarcely 

 •5 to •3mm. broad. Leaves, when dry, flexuose or curled; lamina o:enerallv 2 cm. lono: 

 by '3 mm. broad, sometimes reaching 3'5 cm. by -6 mm., each margin bearing about 12 

 teeth, or sometimes as many as 18, which are shortly projecting, shallowly triangular 

 outgrowths, ending in an ascending brown spine, the whole \ to f of the leaf-width in 

 the lower part of the lamina, becoming more prominent above as the leaf-width 

 diminishes. Sheaths 35 to 5 mm. long by 2 to 3 mm. broad, when opened out, usually 

 with broadly rounded shoulders bearing numerous (10 to 16) small teeth, Intra- 

 vaginal scales tapering slightly to a blunt apex, '75 mm. long. Male floioers absent. 

 Ova7^y 1-75 mm. long. Fruit 2-75 mm. long, pericarp closely enveloping the seed, 

 which is marked with about 25 regular parallel rows of square areohe, not visible on the 

 raphe. 



Very near the Malayan N.foveolata, but distinguished by the very lax habit, rounded 

 leaf-sheath, and slender seed with smaller markings. 



3s2 



