514 WILSON EXPEDITION TO CHINA 
cliffs, alt. 3000 m., October 1910 (No. 4262; bush 1-1.5 m. tall); Lifan 
Ting, thickets, alt. 2500 m., November 1908 (No. 1320; bush 2.5 m. 
tall); Tsaku-lao-ch'u-shin-kou, A. von Rosthorn (No. 2556); without 
precise locality, A.von Rosthorn (Nos. 2147, 2146, 2545,2162). Shensi: 
Tai-pei-shan, 1910, W. Purdom (No. 2); Thui-kio-san, October 1897 
and Si-ku-tzui-stan, 1895, G. Giraldi; various localities, Hugh Scallan. 
Chili: Weichang, 1909, W. Purdom (Nos. 50, 55). 
This pretty and well-marked species although it has a remarkably wide dis- 
tribution exhibits very little variation. With the number of specimens before 
us we cannot separate R. Rosthornii Diels and R. Pritzelianum Diels as distinct 
species or even as varieties. The slight differences in size of calyx-teeth and in 
color of anthers are of no value. Specimens from northern Chili show these same 
slight variations. 
Rhododendron longistylum Rehder & Wilson, n. sp. 
Frutex 0.5-2 m. altus ramis gracilibus; ramuli hornotini sparsissime 
lepidoti, apicem versus puberuli, annotini flavido-fusci v. pallide pur- 
pureo-fusci, vetustiores cinerascentes; gemmae ovoideae, perulis 
apice obtusiusculis v. rotundatis mucronatis extus minute puberulis 
sparse lepidotis ciliolatis. Folia coriacea, oblanceolata v. oblongo- 
lanceolata, rarius elliptico-oblongis, acuta v. brevissime acuminata, 
basi cuneata, 2.5-6 cm. longa et 1-2 cm. lata, supra luteo-viridia, 
nitidula, leviter rugulosa, sparsissime lepidota v. glabra, subtus palli- 
diora, sparse lepidota, costa media supra impressa subtus elevata, 
nervis utrinsecus 6-10 supra leviter impressis indistinctis subtus obso- 
letis; petioli 2-4 mm. longi, puberuli, interdum fere glabri, sparsissime 
lepidoti. Flores 10-20 v. plures, umbellato-racemosi, rhachi circiter 
1 em. longa; pediceli 8-15 mm. longi, sparse glanduloso-lepidoti; 
calyx membranaceus, sparsissime lepidotus, lobis 5 interdum spat 
sissime longe ciliatis ovalibus circiter 2 mm. longis (in specimine 
fructifero ad 5 mm. longis et oblongis); corolla (paucae defloratae 
tantum visae) infundibuliformis, 1.3-1.5 longa ac lata, glabra, lobis 
5 ovalibus 6-8 mm. longis obtusis; stamina 6-10, exserta, filamentis 
1.5-2 cm. longis infra medium villosis, antheris ovoideis ochracels; 
ovarium ovoideum, lepidotum; stylus valde exsertus, 2.5-3 cm. 
longus, gracilis, glaber, stigmate discoideo lobato. Capsula comici 
8-9 mm. longa et 5 mm. diam., apice truncata, lepidota, calyce per 
sistente suffulta; semina flavida, oblonga, 1-1.5 mm. longa, utrinque 
breviter alata. 
Western Szech'uan: west and near Wén-ch'uan Hsien, thickets, 
alt. 2300 m., July and October 1908 (No. 1204, type); same locality; 
