19211 REHDER, NEW SPECIES, VARIETIES AND COMBINATIONS 37 



25 cm. long; rachis densely short-villose; pedicels 1-1.2 cm. long, spread- 

 ing at a right or somewhat acute angle, rather stout, straight, finely vil- 

 lose; calyx about 7 mm. broad and 5-6 mm. high, finely villose, 2-lipped, 

 the lower lip 3-lobed with broadly triangular, subulate-acuminate lobes, 

 the middle one about 4 mm., the lateral ones 2.5 mm. long; corolla pale 

 violet, wings and keel darker, slightly fragrant, standard about 2 cm 

 across and slightly shorter, with rather thin slightly recurved ligular ap- 

 pendages; wings with the claw 1.7-1.8 cm. long; keel 1.5 cm. long. Pod 



* 



7-8.5 cm. long, and 1.8-2 cm. wide at the apex, gradually attenuated 

 toward the base, densely tomentose, usually 1-seeded. 



Cultivated at Holm Lea, Brookline, Mass.; specimens collected May 27 and 

 September 12, 1921, preserved in the herbarium of the Arnold Arboretum. 



This handsome hybrid originated at Holm Lea about 1905 from seed 

 of Wistaria floribunda f. alba Rehd. & Wils. planted by Charles Sander 

 and apparently fertilized by pollen of W. sinensis flowering simultaneously 

 in the greenhouse. The hybrid is nearly exactly intermediate between 



these two species. From W. sinensis Sweet it is easily distinguished by 

 the larger number of less pubescent leaflets (7-11 in W. sinensis), by the 

 longer racemes, the shorter pubescence of the rachis, the long-acuminate 

 lobes of the lower lip of the calyx and by the smaller corolla. From IV. 

 floribunda it differs chiefly in the smaller number of leaflets narrowed 

 toward the base (13-17 and usually rounded at the base in W. floribunda), 

 in the shorter racemes, the shorter and stouter pedicels, the larger corolla, 

 and in the thinner slightly recurved appendages of the standard. 



The hybrid as an ornamental plant is superior to both parents, as 

 the racemes are longer than those of W. sinensis and fuller, though 

 shorter than those of W. floribunda (W. multijuga Van Houtte), because 

 the flowers of each raceme all open almost at the same time, while in 

 W. floribunda the basal flowers are already dropping, before the termi- 

 nal ones have opened. 



Robinia pseudoacacia L. f. unifoliola Talou in Ilorticulteur Franc;, 



1859, 157, as var.* — R. pseudo-acacia monophylla Carriere in Rev. Hort. 



1860, 630, fig. 121, 122.— Hartwig & Ruempler, Baume & Strauch. 490 



(1875), as var. — Voss, Vilmorin's Blumengart. i. 218 (1894), as forma. — 

 R. monophylla Jaeger, Ziergeh. 461 (1865). — R. Pseudacacia heterophylla 

 hort. ex Beissner, Schelle & Zabel, Ilandb. Laubholz-Ben. 271 (1903). 

 The oldest varietal name for the interesting form generally known as 



ifoliola 



It was raised about 



1855 by Deniau of Brain-sur-1'Authion, Maine-et-Loire, (according to 

 Carriere) or, of Angers (according to Talou) and offered to the trade by 

 Lebigot of Angers about 1859. About 1880 two variations of this form 

 one with upright and one with pendulous branches were raised from seed 

 of this form by Dr. G. Dieck, of Zoschen, Germany, for which I propose 

 the following names as those given by Dieck are preoccupied. 



