PTEROCARVA 263 



or oval,, very obliqely tapered or rounded at the base, pointed or blunt at the 

 apex, finely toothed ; 2^ to 5 ins. long, i to 2| ins. wide ; dark glossy green, 

 and smooth except for fine down on the midrib on both surfaces ; common 

 stalk not winged, downy. Male catkins slender, 2J? to 4 ins. long, frequently 

 in pairs. Fruiting catkin 8 to 10 ins. long, each nut surrounded by a wing, 

 the whole forming a circular disk i| to 2i ins. diameter. 



Native of the mountains of Central China ; discovered by Henry in 1888, 

 and introduced by Wilson for Messrs Veitch in 1901. The fruits of this 

 species are very remarkable, suggesting miniature cymbals ; in having the 

 wing continuous all round the nut, they distinguish it from all other species. 

 Henry says it ought to be hardier than P. stenoptera, as coming from higher 

 elevations. Seeds were again sent by Wilson during his later journeys. 



P. REHDERIANA, C. K. Schneider. 



A hybrid between P. caucasica- and P. stenoptera, raised in the Arnold 

 Arboretum, near Boston, Mass., from seeds received in 1879 from the late 

 M. Lavallee's collection of Segrez, where the cross had no doubt been effected 

 by wind on trees growing together. As the seeds were received as 

 P. stenoptera, that species was no doubt the mother plant. I saw the original 

 hybrid in the Arnold Arboretum in June 1910. It is now 40 ft. high and, 

 owing to the property of producing sucker-growths from the root, is forming 

 by itself quite a grove. At least one of the parent species has the same 

 faculty rarely developed, however, unless the main stem is cut down. 

 P. Rehderiana is intermediate between the parents. The common stalk of 

 the leaf has wings, but they are not so much developed as in P. stenoptera, 

 and never toothed as they often are in that species. The wings of the fruit 

 are shorter and rounder. In the Arnold Arboretum this hybrid has proved 

 hardier and a better grower than either of its parents. Living plants were 

 introduced to Kew in 1908. 



P. RHOIFOLIA, Siebold. JAPANESE WlNG-NUT. 



A tree 80 to 100 ft. high, trunk 8 to 10 ft. in girth ; young shoots smooth. 

 Leaves 8 to over 12 ins. long, composed of eleven to twenty-one leaflets, which 

 are rounded at the base, pointed at the apex, oblong, finely and evenly toothed, 

 2| to 4 ins. long, i to i^ ins. wide ; common stalk not winged. The stalk and 

 leaves vary in regard to pubescence, the plants at Kew are smooth except for 

 tufts of stellate down about the midrib and axils of the veins beneath ; but in 

 Japan a form is commonly much more downy on the leaves and leaf-stalks. 

 Male catkins 3 ins. long ; females 8 to 10 ins. long ; wings of the nut horizontal, 

 broadly crescent-shaped, the whole fruit to i in. across. 



Native of Japan ; introduced in 1888. It is quite hardy, and in a moist 

 loam would apparently grow well. Professor Sargent found it abundant on 

 Mt. Hakkoda at 2500 to 4000 ft. above sea-level, and almost the largest 

 deciduous tree in that part of Japan. 



P. STENOPTERA, De Candolle. 



A tree 50 to 60 ft. high, with a fissured trunk 6 to 8 ft. in girth ; young 

 shoots and common stalk of the leaf of some plants furnished with pale hairs 

 persisting through the first winter, but in others both are quite smooth. 

 Leaves 8 to 15 ins. long, composed of eleven to twenty-one (sometimes twenty- 

 five) leaflets, which are oblong or narrowly oval, tapered at both ends, finely 

 and regularly toothed, 2 to 5 ins. long, \ to 2 ins. wide ; the common stalk 

 winged in the spaces between each pair of leaflets, the wings sparsely toothed. 

 Male catkins 2| ins. long ; female ones 8 ins. long. Nut roundish oval with a 



