ONAGRACE.E. 



39 



. . Ovary* 



Calyx tube. 



Calyx lobes. 

 Bifid petals. 



OXAGRACEJE. 



Herbs (shrubby exotics), with the 

 parts of the flowers usually in fours, 

 the calyx tube adnate to the ovary, 

 the petals borne on its throat, and the 

 stamens as many or twice as many. 

 Style always single. In Jussiaea the 



FIG. A. Clarkia elegans ; a, inferior, sessile ovary 

 of the axillary flower. Fig. B. Boisduvallia densi- 

 flora; c, inferior ovary, sessile in the axil of a bract. 

 Fig. C Capsule of Godetia; 6, cross section of the 

 same. Fig. D. Epilobium paniculatum; h, infe- 

 rior ovary ;/, a grown capsule; g, tube of calyx 

 above the ovary; e, one of the bifid petals; i, one 

 of the seeds bearing a tuft of silken hairs. The fig- 



flower parts vary in number from 4 to ure on tne left is a common form of Zauschneria. 

 6; in Circaea the parts are in twos. Many of our plants blossom late .in the dry 

 season. These usually have hard stems from which a shedding, thin, outer bark hangs 

 in shreds. Key to genera and species, p. 124. 



JUSSI^EA. 



J. repens, L., var. Californica, is J. diffusa, Forsk., in Bay-Reg. Bot. It grows 

 in floating masses on stagnant water or along the edges of ponds. 



LUDWIGIA. 



L. palustris, Linn., is Isnardia palustris in Bay-Reg. Bot. Leaves oval or ovate, 

 acute, 6-12 lines long: sessile flowers, solitary in the axils: petals when present, minute. 

 Muddy borders of ponds or watercourses. 



ZAUSCHNERIA. 



Z. Californica, Presl. Decumbent stems, often many together, from a woody base, 

 Branching, more or less hairy: leaves ovate to lanceolate. Blossoming from June to 

 December. (See the figure on the left above.) 



Prof. Greene makes several species of this variable plant. 



