442 WILSON EXPEDITION TO CHINA 
mm. longae, valvatae perulis duobus exterioribus, glabrae, ramulo 
concolores. Folia membranacea, elliptico-oblonga v. oblonga, utrinque 
acuta, integra v. interdum apice tridentata, rarissime pluridentata, 
1-2 cm. longa et 4-8 mm. lata, cinereo- v. pallide luteo-viridia, sub- 
concoloria, utrinque pilis longis villosis densius v. laxius obtecta, nervis 
utrinsecus 2-4 angulo acutissimo divergentibus subtus leviter elevatis; 
petioli 1-2 mm. longi, sparse villosi. Inflorescentia umbellato-race- 
mosa, densa, pluri- v. multiflora in apice ramulorum brevium pauci- 
foliatorum; pedicelli 3-5 mm. longi, villosi; flores albi, circiter 8 mm. 
diam.; calyx extus villosus, tubo intus pubescenti, dentibus late ovato- 
triangularibus intus villosulis; petala rotundata, basi subito contracta, 
vix unguiculata, 3-3.5 mm. diam.; stamina 20, longiora petalis sub- 
aequilonga; carpidia pubescentia, stylum paullo infra apicem gerentia; 
diseus conspicuus, lobatus, purpureus, lobis subglobosis; styli stamina 
dimidia subaequantes. Fructus calyce extus villoso, dentibus re- 
flexis; folliculi erecti, flavescentes, laxe villosi, 1.5 mm. longi, ventre 
gibboso, dorso stylum patenti-erectum paullo infra apicem gerentes. 
Western Szech'uan: north-east of Tachien-lu, ascent of Ta- 
p’ao-shan, alt. 3600-4600 m., July 6 and October 1908 (No. 1158, 
type); Mupin, upland thickets, alt. 2700-3300 m., October 1908 
(No. 1158, in part); Tachien-lu, upland thickets, alt. 3000-3700 m., 
October 1910 (No. 4402); without precise locality, woods and heaths, 
alt. 3000-3700 m., July 1904 (Veitch Exped. No. 3553); alt. 3600-4000 
m., July 1903 (Veitch Exped. No. 3554). 
Allied to S. gemmata Zabel which is easily distinguished, however, by its nar- 
rower glabrous foliage, glabrous inflorescence and slenderer branches. Wilson’s 
No. 3554 differs from the type in the short, not silky-villose pubescence of the leaves 
and may not belong to this species. Spiraea prostrata Maximowicz which has the 
leaves of similar shape and pubescence, differs in its terete branches, small winter- 
buds with imbricate scales and glabrous inflorescence. 
Spiraea laeta Rehder, n. sp. 
Frutex 2-metralis ramis gracilibus virgatis; ramuli hornotini anno- 
tinique glabri, subalato-angulati, purpureo-brunnei, rarius flavido- 
brunnei; gemmae parvae, globoso-ovoideae, pluriperulatae, pubescentes. 
Folia tenuiter membranacea, ovata, v. elliptico-ovata, acuta, basi late 
cuneata v. rotundata, 2-3.5 em. longa et 1-2.5 lata, rarius ad 4.5 cm. 
longa et basi cuneata, incise duplicato-serrata ima basi excepta, apicem 
versus simpliciter serrata, supra glabra, laete luteo-viridia, subtus 
pallide viridia, in axillis venarum subtus barbata et ad nervos sparsis" 
sime in foliis inferioribus interdum densius adpresse pilosa, rarius 
