Fig. 34: Potamogeton crispus: a, habit, X %; b, branch with maturing spikes, 

 X 7.-,; c, few-flowered spike, X 4; d, young flowering spike, emerging from sheathing 

 stipules, X 3; e, winter bud, showing fleshy stems, short internodes and thickened 

 foliaceous bud scales with strongly dentate broadened bases, X 1%; f, stem (cross 

 section), X 6; g, ligulate stipule, X IV2; h, young leaf, showing venation, X 3, i, 

 achene, (longitudinal section), X 6; j, achene, showing the somewhat curved beak and 

 variation in the denticulate dorsal keel, X 6. (From Mason, Fig. 21). 



