396 CONTRIBUTIONS FROM THE NATIONAL HERBARIUM. 
Rance: Utah to Arizona and New Mexico. 
New Mexico: Ramah; San Lorenzo; Magdalena Mountains; Horse Camp; Tunitcha 
Mountains; Willow Creek, Rio Arriba County. Meadows. 
5. Tithymalus chamaesula (Boiss.) Woot. & Standl. Contr. U. 8. Nat. Herb. 16: 
145. 1913. 
Euphorbia chamaesula Boiss. Cent. Euphorb. 38. 1860. 
TYPE Locality: Near the Copper Mines, New Mexico. Type collected by Wright 
(no. 1820). 
Range: Arizona and New Mexico and adjacent Mexico. 
New Mexico: Mogollon Mountains, and south to the Mexican boundary. Tran- 
sition Zone. 
6. Tithymalus montanus (Engelm.) Small; Rydb. Colo. Agr. Exp. Sta. Bull. 100: 
224. 1906. 
Euphorbia montana Engelm. in Torr. U. S. & Mex. Bound. Bot. 192. 1859. 
Euphorbia montana gracilior Engelm, loc. cit. 
Tyre Locality: Near Santa Fe, New Mexico. Type collected by Fendler (no. 786). 
Rance: Utah and Colorado to Arizona and western Texas. 
New Mexico: Farmington; Sandia Mountains; Chama; Santa Fe and Las Vegas 
mountains; Black Range; San Luis Mountains; White and Sacramento mountains. 
Meadows, in the Transition Zone. 
The type of EL. montana gracilior was collected near Santa Fe (Fendler 786, in part). 
3. TITHYMALOPSIS Klotzsch & Garcke. 
Slender glabrous perennial herb with erect stems and oblong-linear alternate leaves; 
involucres on pubescent pedicels 3 to 5 mm. long, clustered; glands sessile or stalked, 
with yellowish white appendages; capsule exserted; seeds narrowed upward, more or 
less punctate, without caruncles. 
1. Tithymalopsis strictior (Holzinger) Woot. & Standl. 
Euphorbia strictior Holzinger, Contr. U. 8. Nat. Herb. 1: 214. pl. 18, 1892. 
Type LocaLity: Oldham County, Texas. 
Rance: Texas to eastern New Mexico. 
New Mexico: Tucumcari Mountain; Nara Visa. Plains and hills, in the Upper 
Sonoran Zone. 
4. DICHROPHYLLUM Klotzsch & Garcke. SNOW-ON-THE-MOUNTAIN. 
Annual with erect stems umbellately branched above, 40 to 80 cm. high; leaves alter- 
nate or opposite, sessile, ovate, entire, acute, about 5 cm. long, those of the inflorescence 
broadly white-margined, attenuate below into a short petiole; flowers crowded at the 
summit of the stem; involucres campanulate, in rather dense cymes, the lobes fimbri- 
ate, the 5 glands peltate, somewhat concave, with pink and white petal-like append- 
ages; capsule exserted, pubescent; seeds narrowed upward, carunculate. 
1. Dichrophyllum marginatum (Pursh) Klotzsch & Garcke, Monatsb. Preuss. 
Akad. Wiss. Berlin 1859: 249. 1859. 
Euphorbia marginata Pursh, Fl. Amer. Sept. 607. 1814. 
Tithymalus marginatus Cockerell, Univ. Mo. Stud. Sci. 22: 165. 1911. 
Type Loca.ity: ‘‘On the Yellow-stone river.”’ 
Rance: Montana and Minnesota to New Mexico and Texas. 
New Mexico: Frio Draw; Tucumcari; Red Lake east of Elida; Albert; Roswell. 
Plains, in the Upper Sonoran Zone. 
A showy plant, not rare in cultivation. It is easily recognized by the white- 
margined floral leaves. 
