Naias.~\ CLXX. NAIADACE.E. (J. D. Hooker.) 569 



to the inner perianth, apiculate or cuspidate, 1-4-celled. Fern, perianth 0, 

 or hyaline and adherent to the carpel. Carpel 1, sessile, 1-ovuled ; stigmas 

 2-4, slender ; ovule basilar, erect, anatropous. Achene oblong. Seed 

 erect, testa very thin ; embryo straight. Species about 10, temperate and 

 tropical. 



The Indian species of this genus require a very close examination, which I regret 

 to say I have not materials in flower and fruit sufficient to enable me to undertake. 



1. N. major, All. FL Pedem. ii. 221; stem terete toothed, leaves 

 linear almost pinnatifidly toothed, teeth triangular, base hardly dilated, 

 flowers solitary, anther 4-celled. Kunth Enum. iii. 112 ; Nees Gen. Fl. 

 G-erm. iii. t. x. ; in Linnsea, ix. t. 7, and x. t. 1 ; Boiss. Fl. Orient, v. 

 27. N. fucoides, Griff. Notul. iii. 184; Ic. PL Asiat. t. 251, f. 1. 1ST. 

 muricata, Del. FL Egypt. 281. N. spinosa, Ham. in Wall. Cat. 5182. 



Throughout India, in fresh and brackish water, ascending to 8000 ft. in Western 

 Tibet. CEYLON. DISTRIB. Europe, Asia, Africa. 



Stem terete, branched. Leaves |-li in., teeth 4-8 on each side, dorsally spinous; 

 sheath with rounded entire sides. Flowers dioecious ; invol. of male oblong, 2-3- 

 toothed. Carpel oblong, stigmas 2-3, filiform. Achene T \-g- in. 



2. N. graminea, Del. Fl. Egypt. 282, t. 50, f. 3 ; leaves narrowly 

 linear or subulate acuminate flaccid acutely many-toothed, basal auricles 

 erect lanceolate toothed on both margins, flowers fascicled monoacious, 

 anthers 4-celled. Kunth Enum. iii. 11 5; Boiss. FL Orient, v. 28 ; A. Braun 

 in Seem. Journ. Bot. ii. (1864) 278, f. 5. N. seminuda, Griff. Notul. iii. 

 184 ; Ic. PL Asiat. t. 251, f. 2, and t. 253, 254. N. semistipula, Ball. FL Ticin. 

 t. 15. Caulinia alzanensis, Pollin. FL Veron. iii. 49. Fluvialis indica, 

 Pers. ex Wall. Cat. 5183 B. 



Throughout INDIA in still fresh water, and CEYLON. DISTRIB. the Old World 

 generally. 



Stem 1-2 ft. Leaves f -1 in., usually whorled, broader, more transparent and 

 more acutely toothed than is N. minor. 



3. N. minor, All. Fl. Pedem. ii. 221 ; leaves very narrowly linear 

 remotely toothed basal auricles rounded or truncate toothed rarely acute 

 and entire, flowers fascicled monoecious, anther 1-celled. Kunth Enum. iii. 

 113 ; Nees Gen. FL Germ. iii. t. x. ; Boiss. Fl. Orient, v. 28. N. dichotoma, 

 Roxl. Fl. Ind. iii. 749. N. ternata, Roxb. ex Gri/. Notul. iii. 183 ; Griff. 

 Ic. PL Asiat. t. 252. N. indica, Cham, in I/inntea,iv. 501. Caulinia indica, 

 and fragilis, Willd. in Mem. Acad. Berl. (1798) 89. C. indica, Wall. Cat. 

 5183, in part. 



Throughout INDIA and CEYLON, in still sweet water. DISTRIB. Old World 

 generally. 



Stem very slender, much branched. Leaves spreading, or the upper recurved, 

 ^ in. or less, hardly ^y in. broad, green or brown when dry. There may be two 

 or more species in India under the above name. The other plant under Wallich's 

 5183 is a Chara. 



4. N. falciculata, A. Braun in Seem. Journ. Bot. ii. (1864) 278, f. 4 ; 

 stem rigid, leaves as in N. minor, but auricles falcately incurved entire or 

 the inner margin entire the outer toothed. 



MADRAS ; at Tuticoreen, Wight. DISTRIB. Philippine Islands. 



I greatly doubt this being distinct from N. minor, amongst numerous specimens 

 of which I find some with basal auricles very like those figured by Braun as falci- 

 culata. 



