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MEMOIRS OF THE NEW YORK BOTANICAL GARDEN 



{Vol. 9, No. 2 



have been collected. Although these collections were made throughout the growing 

 season, none of them seem to bear mature achenes, which suggests hybrid-sterility. 



The starchy, large winter-storage corm was extensively used as food by the 

 North American Indians. In California the Chinese and Japanese probably still use 

 them as vegetables. This may explain its presence in the Hawaiian Islands where 

 it is well established although previously misidentified as 5. sagittifolia L. The 

 plant was probably introduced there by some of the numerous orientals who settled 

 in Hawaii after discovering that California was not their land of opportunity. 



16. Sagittaria longiloba Engelm. ex Torr. in J.G.Sm. Missouri Bot. Gard. Rep. 

 6: 16. 1894. 



Sagittaria sagittifolia var. mexicana Martens & Gal. Bull. Acad. Roy. Brux. 9(2): 379. 

 1842. 



Sagittaria sagittifolia var. variabilis (Engelm.) Micheli in DC. Monogr. Phan. 3: 69, 

 p.p. 1881. 



Sagittaria greggii J.G.Sm. Missouri Bot. Gard. Rep. 6: 17. 1894. 



Perennial with rhizomes and/ or runners with corms. Leaves emersed, sagit- 

 tate, with linear to ovate- triangular blades 3-15 x 1.3-10 cm, the linear to lanceo- 

 late basal lobes 8-21 x 0.6-7 cm, always longer than and commonly twice as 

 long as the blades, the petioles 35-75 cm long. Scapes 35-140 cm long, with 

 4-12 whorls of flowers, commonly branching at the lowest whorl. Bracts linear, 

 elongate, 0.8-5 cm long, joined at the base, the free ends often reflexed. Pedicels 

 1-3.5 cm long, ascending. Sepals 0.4-0.7 cm long, reflexed. Petals white, ca. 

 twice the length of the sepals. Stamens 15- °s the glabrous, linear filaments 2-3 

 mm long, exceeding the nearly linear anthers. Mature receptacle 0.7-1.2 cm in 

 diameter; achenes obovate, 1.2-2.3 x 0.6-1.3 mm, the narrow dorsal wing to 0.3 

 mm wide, the ventral wing nearly obsolete, the faces commonly 1-winged, the 

 short, triangular, laterally inserted beak to 0.15 mm long, or obsolete. 

 (FIG. 19a-c.) 



Type collection: Gunnison Expedition 49, *Western Texas' (holotype NY; 

 isotype GH). Although the collection label is marked Western Texas, field notes 

 state 'Upper Arkansas (River)*; therefore the plant probably was collected in 

 Colorado. Engelmann proposed S. longiloba for Torrey's Botany of the Mexican 

 Boundary Survey. Torrey in a footnote in that work described the plant and credited 

 Engelmann with the name, at the same time stating that the plant was not distinct 

 and failing to maintain it. Therefore, although published and adequately described, 

 the name was not validly published until J. G. Smith included it in his revision of 

 the genus. 



Distribution: Nebraska and California, south to Mexico, but absent in the Rocky 

 Mountains and the Great Basin. A common plant of the southern Great Plains and 

 Mexico, in the shallow waters of sloughs, swamps, ponds, and ditches. Collec- 

 tions examined from Arizona, California, Colorado, Kansas, Nebraska, Oklahoma, 

 and Texas in the United States, and Guanjuato, Michoacan, Oaxaca, Queretaro, 

 Sinaloa, Sonora, and Tamaulipas in Mexico. (FIG. 19.) 



One of the few species of Sagittaria with relatively constant leaf-shape, S. 

 longiloba is easily recognized by the elongate basal lobes of the invariably sagit- 

 tate leaves. It is related to S. latifolia and other members of the subgenus with 

 glabrous filaments and sagittate leaves. The short, laterally inserted beaks of the 

 rather small achene are quite distinctive. 



Sagittaria greggii J.G.Sm. is here included in synonymy on the basis of similar 

 vegetative and floral characteristics. It is not given varietal or subspecific rank, 

 even though, to a degree, the Californian and Mexican plants on which Smith based 



