Fig. 50: Najas marina: a-c, development of anther: a, anther enclosed in sessile 

 spathe in leaf axil, X 8; b, anther beginning to elongate and rupture spathe, X 8; c, 

 mature anther, showing short filament, X 8; d, habit, showing the stems beset with 

 prickles, and the spiny-toothed leaves, X 1%; e, mature pistillate flower, showing the 

 3 stigmas and the intravaginal scales at base, X 8; f, mature seed, X 10: g, leaf blade, 

 showing the coarse, spiny-toothed margins, the spines on the outer side along the 

 midrib, and the rounded shoulders of the leaf sheaths, X 6. (From Mason, Fig. 33). 



