Sparganium eurycarpum
 
Giant Bur-Reed

Pistil

Saginas Lake Dam, South of Hudson Bay on Highway # 982
27-June-2019

Note that most flowers, including this one, have two stigmas.  All the tepals have been removed from this specimen.

See here for a key to Saskatchewan Sparganium species created by Anna Leighton and found in Rushes, Bulrushes & Pondweeds plus the remaining Monocots of Saskatchewan by V.L. Harms,  A.L. Leighton and  M.A. Vetter)

bullet

Eurycarpum: Answers to key questions in Rushes, Bulrushes & Pondweeds plus the remaining Monocots  of Saskatchewan by V.L. Harms, A.L. Leighton and M.A. Vetter leading to this species. The answers are in the order you would normally work through the key.
bullet

Stigmas usually 2, occasionally 1 on some flowers; mature fruit bodies 5-10 mm long, obpyramidal, abruptly contracted to beaks, sessile, usually 2-locular and 2-seeded; inflorescences usually branched; leaves emergent; NOT [Stigmas 1; mature fruit bodies usually <5 mm long, ellipsoidal, fusiform or obovoid, tapering to beaks (+/- beakless in S. hyperboreum), stipitate or subsessile, 1-locular and 1-seeded; inflorescences branched or unbranched; leaves emergent or floating]