ERICACEAE. — RHODODENDRON 529 



Rhododendron Thayerianum Rehder & Wilson, n. sp. 



Frutcx 3-4-metralis, ramulis crassiusculis puberulis plerumquc ab- 

 breviatis foliis congestis; pcrulae per plures annos persistentes,oblongae 

 V. oblongo-spathulatae v. lanceolatae, acutae v. obtusae v. apiculatae, 

 1-2 cm. longae, glabrae v. extus sericeae, brunneae. Folia coriacea, 

 anguste oblanceolata, cuneata, acuminata, 8-13 cm. longa et 1.5-3 cm. 

 lata, supra laete viridia, nitidula, leviter elevato-reticulata, subtus 

 tomento crustaceo pallidc brunneo denso obtecta, costa media supra 

 impressa subtus elevata fere glabra, nervis utrinsecus 10-12 obsoletis 

 interdum supra leviter impressis; petioli crassiusculi, initio sparse 

 glandulosi demum glabri, 1-1.5 cm. longi. Flores 10-15, racemosi; 

 rhachis elongata, satis gracilis, 3-3.5 cm. longa, sparse stipitato- 

 glandulosa ut pedicelli graciles, 4-5 cm. longi; bracteae oblongo-spa- 

 thulatae V. oblongae, 1-2.5 cm. longae, extus sericeae ad maturitatem 

 fructus persistentes; calyx cupularis, lobis inaequalibus semiorbicu- 

 laribus 1.5-2 mm. longis glandulosis; corolla infundibuliformis, 

 5-lobata, 2.5-3 cm. longa et 3-3.5 cm. diam., lobis inaequalibus cir- 

 citer 1.5 cm. longis rotundatis; stamina 8-10, corollam fere aequantia, 

 filamentis 2-2.5 cm. longis compressis in dimidio inferiore floccoso- 

 villosis; ovarium elongatun, glandulosum; stylus rectus, circiter 2.5 cm. 

 longus, dense glandulosus, stigmate magno applanato. Capsula cylin- 

 drica, 2-3 cm. longa et circiter 6 mm. diam., 6-8-locularis, glandulosa; 

 semina anguste oblonga, 3-4 mm. longa, pallide brunnea, utrinque alata. 



Western Szech'uan: Mupin, woodlands, alt. 3000 m., October 

 1910 (No. 4273). 



This is a remarkably distinct species differing from all allied species in its per- 

 sistent bud-scales densely covering the leafy shoots. The leaves are crowded and 

 the inflorescence and ovary are very glandular. In its dun-colored, crust accous 

 tomentum this new species resembles R. longipcs Rehder & Wilson, which is, 

 however, readily distinguished by its differently shaped flowers and leaves, de- 

 ciduous bud-scales and bracts, glabrous non-glandular stamens and style. Our 

 specimens are in ripe fruit with a few old flowers adherent to the glandular 

 capsules. 



This species is named for the Thayer family of Lancaster, Massachusetts, 

 prominent in horticulture and generous in its support of the explorations in China 

 undertaken by the Arnold Arboretum. 



Group b. 



Leaves with a woolly or sometimes nearly scurfy brownish tomentum on the 

 midrib beneath, otherwise glabrous or villose when young. 



Rhododendron longesquamatum Schneider, ///. Handb. Laubholzk. 

 II. 483 (1909), 1045 (1912). 



