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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN [Vol. 9, No. 2 



from the western slopes of the Appalachian Mountains. The extreme tidal form of 

 subsp. spongiosa is a unique dwarfed plant characterized by lanceolate or spatu- 

 late phyllodia and a scape of 1-3 whorls of flowers (L. spatulatus J.G.Sm.). 

 Southwards from Connecticut, an enlarged, emersed, sagittate-leaved form occa- 

 sionally appears in less brackish waters that is impossible to separate from 

 subsp. calycina except on the basis of geography and ecology. 



The confused synonymy of the species is due to the very plastic vegetative 

 characteristics, such as leaf-shape and phyllodial modifications resulting from 

 edaphic conditions, and, as seen previously in S. guyanensis, to the wide geo- 

 graphic range and the indecision on generic limits. The presence or absence of 

 pubescence on the filament is of only doubtful value in determining the various 

 subspecies, since in many cases it is lost in preparing the plants for mounting 

 (Mason 1952). The presence of functional stamens in the pistillate flower is too 

 erratic to be of real use. The position of the beak and the facial adornment are 

 equally valueless as a means of identification, since all grades of intermediates 

 have been collected. It should be stressed, however, that the combination of these 

 characteristics is usually correlated with the geographical distribution and will, 

 in a great majority of the cases, satisfactorily identify the plant. The key to the 

 subspecies presented above has been formulated on this basis. 



5. Sagittaria sanfordii Greene, Pittonia 2: 158. 1890. 



Perennial with runners and perennating corms. Leaves typically emersed, 

 mostly linear, occasionally with lanceolate to ovate or obovate blades 5- 16 x 1.5-6 

 cm, the submerged leaves modified into phyllodia to 50 cm long, gradually taper- 

 ing above; petioles 30-70 cm long. Scape simple with 3-8 whorls of flowers. 

 Bracts connate, 0.4-0.6 cm long, their free ends triangular. Pistillate flowers 

 with thickened recurved pedicels 1.5-2.5 cm long; sepals small, 0.4-0.6 cm long, 

 spreading, scarcely covering a fourth of the receptacle at maturity; petals white, 

 about twice as long as the sepals. Staminate flowers with filiform divaricate 

 pedicels 1.5-3 cm long; stamens 15-°s the slightly dilated filaments about 1.2 

 mm long, pubescent, the oblong anthers the same length or slightly longer. Mature 

 pistillate flowers 0.8-1.3 cm in diameter; achenes obovate to nearly orbicular, 

 2-2.6 x 1.2-2 mm, the dorsal wing 0.3-0.5 mm wide, the ventral wing somewhat 

 narrower, the faces unadorned, or with a single low wing, the short, broad-based 

 beaks 0.2-0.5 mm long, vertically or obliquely inserted, occasionally obsolete. 

 (FIG. 7 a, b.) 



Type collection: 1890, Sanjord s.n., Stockton, San Joaquin Valley, California 

 (holotype, not seen, presumably in Herb. Greeneanum, University of Notre Dame; 

 presumed isotype, UC). No plant from Herbarium Greeneanum was seen, but the 

 plant at UC was labeled as this by Greene without signifying if it was part of the 

 type collection. 



Distribution: The Great Valley of California, in fresh to alkaline waters of 

 sloughs, ponds and ditches. (FIG. 7.) 



One of the few truly localized species of Sagittaria; the others, S. demersa 

 and 5. macrophylla, are both from the same general area and of fairly close re- 

 lationships. All three are apparently quite abundant within their limited range. 

 Sagittaria sanfordii and S. demersa, S. intermedia, and S. subu\ata form a more or 

 less intermediate group between the more primitive members of the subgenus 

 Lopbotocarpus and the subgenus Sagittaria, The group is characterized by the 

 gradually increased spreading of the sepals away from the pistillate receptacle, a 

 tendency for the pistillate pedicels to become less thickened, and a uniformly 

 northern-New-World, warm- temper ate or semi-tropical distribution. S. sanfordii is 



