150 COMPOSITA. 
85. HYMENOCLEA. 
Hymenoclea, Torr. et Gray in Gr. Pl. Fendl. p. 79; Benth. et Hook. Gen. Plant. ii. p. 354. 
Two shrubby species, inhabiting the countries immediately to the north of Mexico, 
and one extending into Mexico. 
1. Hymenoclea monogyra, Torr. et Gray in Gr. Pl. Fendl. p. 79. 
Cauirornia; New Mexico; Texas.—Norta Mexico, Ojito (Gregg), valley of the Gila 
(Zorrey), Chihuahua (Potts). Hb. Kew. 
86. AMBROSIA. 
Ambrosia, Linn. Gen. Plant. n. 1057; Benth. et Hook. Gen. Plant. ii. p. 354. 
Bentham and Hooker estimate the number of species at about twelve, though many 
more have been proposed. They are herbs; and all, or nearly all, inhabit America, one 
or two being also very widely dispersed in the temperate and hot regions of the Old 
World. 
1. Ambrosia artemisizfolia, Linn. Sp. Pl. p. 1401; Lamk. Ill. t. 765. £1; 
DC. Prodr. v. p. 526. | . | 
A common plant from New Jersry and the Rocky Mountains, southward to—Norta 
Mexico, region of San Luis Potosi, 6000 to 8000 feet (Parry & Palmer, 4334), Mata- 
moros (Berlandier); Sour Mexico, region of Orizaba (Bourgeau, 2810), Morelia, 
6000 feet (Galeotti, 285), Tacubaya (Schaffner); Nicaragua, Tortuga (Grsted).— 
Southward to Urvevay and in the Wust Inpies; also in the SANDWICH IsLANDS, where, 
however, it may have been introduced. Hb. Kew. 
2. Ambrosia cheiranthifolia, A. Gr. in Torr. Bot. U.S. & Mex. Bound. Surv. 
p. 87. 
NortH Mexico, San Fernando, Coahuila (Berlandier, 1543, 3043). 
3. Ambrosia confertiflora, DC. Prodr. v. p. 526. 
Norra Mexico, Matamoros (Berlandier, 2297). 
4, Ambrosia fruticosa, DC. Prodr. iv. p. 525. 
NortH Mexico, Tamaulipas (Berlandier). 
Var. Canescens, Benth. Pl. Hartw. p. 17. . 
Nortu Mexico, Zacatecas (Coulter, 395); South Muxico, Aguas Calientes (Hartweg, 
121). Hb. Kew. 
5. Ambrosia peruviana, Willd. Sp. Pl. iv. p. 377; DC. Prodr. v. p. 526. 
Sour Mexico, Real del Monte (Henke).—Perv. 
There is some doubt respecting the identity of the Mexican and Peruvian plants. 
