382 



CALLITRICHACEAE. 



[VOL. II. 



I. 



Callitriche Austin! Engelm. 



4 



Terrestrial Water-Starwort. 



(Fig. 2339.) 



Callitriche terrestre Raf. Med. Rep. (II. ) 5: 358. 1808 ? 

 Callitt ichedeflexa var. Austint Hegeltn. Ver. Bot. Ver. Brand. 



p: 15- 1867. 

 C. Austint Engelm. in A. Gray. Man. Ed. 5, 428. 1867. 



Tufted, the branches spreading on the ground or ascend- 

 ing, l /t f -"i' long. Leaves spatulate or obovate, 3-nerved, 

 i^ // -2 // long, about i" wide, obtuse, tapering at the base 

 into a short margined petiole, destitute of stellate scales; 

 fruit about \" long and nearly %" broad, deeply notched 

 at both ends, its lobes with a narrow marginal wing or 

 raised border, with a deep groove between them ; peduncle 

 shorter than or slightly exceeding the fruit; styles per- 

 sistent, not longer than the fruit, spreading or reflexed. 



In damp, shaded places, southern New York and northern 

 New Jersey to Ohio and Missouri, south to Tennessee, Louis- 

 iana, Texas, and Mexico. July-Sept. The dried plant ex- 

 hales a pleasant odor like Melilot. 



2. Callitriche palustris L,. Vernal Water-Starwort. Water Fennel. (Fig. 2340. ) 



Callitriche palustris L. Sp. PI. 969. 1753. 



Callitriche verna L. Fl. Suec. Ed. 2, 4. 1755. 



Callitriche vemalis Koch, Syn. Fl. Germ. Ed. 2, 245. 1837. 



Aquatic or growing in the mud, stems 2 / -io / long. Sub- 

 merged leaves linear, i -nerved, retuse or bifid at the apex, 

 5"-lo" long; emersed or floating leaves obovate, obtuse, 

 truncate or retuse at the apex, narrowed at the base into 

 a margined petiole, dotted with stellate scales; aquatic 

 forms occur with the leaves all linear; fruit 2-bracted, 

 oval, ^"-i" long, about one-half as broad, nearly flat on 

 the face, slightly notched at the apex, winged only to- 

 ward the apex, or all around, separated by a deep groove. 



Mostly in cold or running water, apparently occurring 

 nearly throughout the United States and Canada. Also in 

 South America, Europe and Asia. July-Sept 



3. Callitriche heteroph^lla Pursh. Larger 

 Water-Starwort. (Fig. 2341.) 



Callilriclie heterophylla Pursh, Fl. Am. Sept. 3. 1814. 



Similar to the preceding species, either aquatic or 

 growing in the mud. Fruit smaller, mostly obovate, 

 usually slightly less than ]/*" long, and about the same 

 breadth, broadly notched at the apex, thick, plano-con- 

 vex, almost ventricose at the base; lobes obtusely angled 

 with a small intervening groove, wingless, or with a 

 narrow wing or raised border on the margins; styles 

 usually longer than the fruit, erect. 



In ponds and slow streams, New England to Florida, west 

 to the Northwest Territory, Missouri and Louisiana; of more 

 southerly distribution than the last. Also in Colorado. 

 July-Sept. 



4. Callitriche bifida (L/.) Morong. Autumnal 



or Northern Water-Starwort. (Fig. 2342.) 

 Callitriche palustris var. bifida L. Sp. PI. 969. 1753. 

 Callitriche autumnalis L. Fl. Suec. Ed. 2, 4. 1755. 

 Callitriche bifida Morong, Mem. Torr. Club, 5: 215. 1894. 



Entirely submerged. Leaves crowded, linear or linear- 

 lanceolate, clasping at the base, retuse or bifid at the 

 apex, i-nerved, s'MJ" long, without stellate scales; fruit 

 sessile, or rarely minutely pedunculate, orbicular or 

 slightly narrower than long, W~\" in diameter, its 

 lobes separated by a deep groove and broadly winged on 

 the margins; styles as long as the fruit, or shorter, soon 

 deciduous; bracts none. 



In flowing water, Quebec and Lake Champlain to Michi- 

 gan, Manitoba and Oregon, south in the Rocky Mountains to 

 Colorado. Also in Europe and Asia. July-Sept. 



