231 
Tribulus decolor Macfadyen, FI. Jamaic. 186. 1837. 
Distr. Kansas, Arizona, Texas, New Mexico, Florida, Mexico, 
and common in tropical and sub-tropical America to Brazil. 
7..PEGANUM L. Sp. Pl. 444. 1753. 
Prcanum Mexicanum A. Gray, Pl. Wright. 1: 30. 1852. 2: 
106. 1853. 
Distr. New Mexico and Mexico. 
The Genus Zenobia Don, 
In 1834 David Don published « A New Arrangement of the 
Ericaceae,”* in which he separated a number of species from the 
large Linnaean genus Andromeda, creating at the same time sev- 
eral new genera in which the detached species were included. Of 
these additions, Cassandra (now Chamaedaphne), Casstope and 
Leucothoe have long been recognized as distinct; but Zenodia, 
although it was taken up by Bentham and Hooker,} has been 
considered by Gray and later botanists only a subgenus of Andro- 
meda. 1 here propose to restore it to its original rank, thus pre- 
serving the arrangement of Don and of Hooker. 
ZENOBIA Don. 
Calyx free, 5-lobed; corolla campanulate with 5 rounded 
lobes; stamens 10, on short basally dilated filaments; anther- 
cells elongated, 2-awned; stigma simple; capsule depressed-glo- 
bose, 5-angled, loculicidally 5-valved, many-seeded ; seeds oval, 
with a spongy testa and fleshy albumen. Smooth or glaucous 
shrubs with somewhat coriaceous strongly reticulated leaves, and 
white flowers disposed in axillary fascicles. 
ZENOBIA CASSINEFOLIA (Vent.). 
Andromeda cassinefolia Vent. Hort. Cels. 1: 00. 1800. 
Andromeda nitida Sims, Bot. Mag. fl. 970. 1803. Not Bartr. 
Andromeda speciosa Michx. Fl. Bor. Am. 1: 256. 1803. 
Fruticose, glabrous throughout; leaves coriaceous, oblong- 
Ovate, acuminate, irregularly serrate, the earlier obtuse, the later 
acute, length 5 cm., width 2.5-to 3 cm.: flowers in naked umbelli- 
————— 
* Edinb, N. Phil. Journ. 17: 158, 1834. 
+ Genera Plantarum, 2: 587. 1873. 
