20 WILSON EXPEDITION TO CHINA 



patentes; ramuli penduli, annotini obscure pallide flavo-brunnei, 

 glabrij homotini initio sparse pubescentes; gemmae brachyblasticae 

 ovatae, obtusae, avellaneae, nitidulae, basi pilis pallidis circumdatae. 

 Folia fasciculata, 25-40 v. plura^ laete viridia, linearia; supra medium 

 paulo latiora, basim versus sensim angustata, apice acuta v. acutiuscula 

 leviter incrassata, margine leviter recurva, 1.2-3.5, plerumque 2-3 

 cm. longa, circiter quater latiora quam crassa, utrinque carinata, 

 subtus fasciebus 2 stomatiferis leviter glaucescentibus, epidermide 

 leviter papillosa, hypodermide supra contigua, subtus tantum sub 

 carina et marginem versus evoluta, endodermide ovali, fasciculo 

 vasculari cellulis sclerenchymaticis instructo. Strobili numerosi, 

 breviter pedunculatij erecti, maturitate brunnei, 3-4 cm. longi; brae- 

 teae persistentes, triangulariHDvatae, squamis longiores, reflexae, 

 sensim in cuspidem attenuatae, rarius leviter contractae, 10-14 mm, 

 longi, 6-7 mm. lati; squamae numerosae, reniformi-orbiculares, 

 rotundatae v. leviter truncatae, integrae, 6-9 mm. longae et 9-12 mm, 

 latae; semina obovoidea, 2-2.5 mm. longa, alls obovatis rotundatis 

 V. obtusiusculis 6-8 mm. longis nitidulis brimneis. 



Western Szech'uan: west of Kuan Hsien, on the Niu-tou-shan, 

 alt. 2600-3300 m., June 21, 1908, seeds ripe (No. 906, in part, type); 

 west of Kuan Hsien, lower slopes of the Pan-lan-shan, sides of streams, 

 alt. 2000-3300 m., common, June and Jxily 1908 (No. 906, in part); 

 west and near W^n-ch'uan Hsien, woodlandS; alt. 2500-3500 m., 

 October 1910 (No, 4730). 



This new Larcli is closely related to L. Griffithii Hooker f . & Thomson, which is 

 distinguished chiefly by its very much larger cones 5-8 cm. long, with larger bracts 

 abruptly cuspidate at the apex, and by the leaves which have a smooth, not papil- 

 lose epidermis and a continuous hypodenn. 



Larix Potaninii Batalin, the only other and much more common Larch found 

 in western Szech'uan can be distinguished at once by its shining orange-brown 

 or purple-brown branchlets and by the violet-purple color of its ripe cones with 

 shorter, erect bracts. The habit is also less spreading and more pendulous than that 

 of L. Mastersiana and in this respect L. Potaninii more closely resembles L. Grif- 

 fithii. These three species of Larch with the north-west American species L. occi- 

 dentalis Nuttall, and L. Lyallii Parlatore, form a well-marked section of the genus, 

 distinguished by the relatively large cones with exserted bracts. In L. Potaninii, 

 L. occidentalis and L. Lyallii^ the exserted part of the bract is erect; in L. Gn/- 

 fiihii and L. Mastersiana it is strongly recurved. 



Larix Mastersiana is apparently a very local species and is known to us only 

 from the petty tribal state of Wassu, situated immediately west of the Min river 

 north of Kuan Hsien. In this small territory this Larch is abundant, but in 1908 

 and 1910 it was being rapidly cut in the more accessible districts. The timber is 

 esteemed for house building and general construction work and commands a high 

 price at Kuan Hsien. Fortunately the region is extremely precipitous and diffi- 

 cult of access and there is very little possibility of this interesting tree being ex- 



