EMPETBACE^. 213 



Okdeb XCI. EMPETRA'CEiE. (Crowberry FAMiLr). 



Low shrubby evergreens, resembling heaths as to leaves 

 and general aspect. Flowers dioecious or polygamous. 

 Calyx somewhat petal-like or none. Ovary 3-9-celled, 

 berry-like in fruit. 



Synopsis at tlic Oencra. 



1. Eiu'petriim.. Flowers scattered and aolitary In the axils. SepaIsS, 



somewhat petal-like. 



2. Core' ma. Flowers in terminal heads. Calyx none. 



I. EM'PETRinil, Tourn. Crowberby. 

 E. ni'grum, li. (Black Crowberry.) A slender procum- 

 bent shrub with the foliage and aspect of a heath. Flowers 

 polygamous, inconspicuous in the axils of the leaves. Calyx 

 3 petal-lika sepals. Corolla wanting. Stamens 3. Fruit a 

 blackberry-like drupe. — Atl. Prov. and northward. 



2. COKE'lHA, Don. Beoom-Cbowbekky. 

 C. Conrad'ii, Torr. (Broom-Growbbrry.) Closely resem- 

 bling the preceding. Flowers dicBcious or polygamous, col- 

 lected in terminal heads, each in the axil of a scaly bract, 

 having no true calyx, but with 5 or 6 thin, dry bractlets 

 under ejich. Stamens 3 or 4 with slender filaments. Drupes 

 small, juiceless when ripe. — Atl. Prov. 



Order XCII. CERATOPHYLLA'CEiE. (Hornwort F.) 



Sepresented, with us, by a single species. 



CEKATOPHYI'JLITM, L. HOBNWORT. 

 C. demer'SUm, L, An aquatic herb, with whorled finely 

 dissected leaves, and minute axillary sessile monoecious 

 flowers, without calyx or corolla, but with an 8-12-oleft 

 involucre. Staminate flowers of 12-24 stamens with large 

 sessile anthers. Pistillate flowers of a single 1-celled ovary, 

 forming an aohene, beaked with the slender style. Embryo 

 with 4 cotyledons.^-Vnier water in ponds an4 sjpv streams, 



