623 



with the staminal tube, or finally free; anthers ovoid; ovary inserted at the base of the calyx, 

 linear-oblong, stipitate; style subulate, inflexed, bearded along the inner side near the apex, 

 with a small terminal stigma; ovules numerous, suspended from the inner angle of the ovary, 

 in two ranks, superposed. Legumes in drooping many-fruited racemes, many-seeded, linear, 

 compressed, almost sessile, 2-valved, the seed-bearing suture narrow-winged; valves thin 

 and membranaceous. Seed oblong-oblique, transverse, attached by a stout persistent 

 incurved f unicle enlarged at the point of attachment to the placenta ; seed-coat thin, crusta- 

 ceous; albumen thin, membranaceous; cotyledons oval, fleshy; radicle short, much re- 

 flexed, accumbeht. 



Robinia with seven or eight species is confined to the United States and Mexico; of 

 the species found in the United States three are arborescent. 



The generic name commemorates the botanical labors of Jean and Vespasien Robin, 

 arborists and herbalists of the kings of France in the sixteenth and seventeenth centuries. 



CONSPECTUS OF THE ARBORESCENT SPECIES OF THE UNITED STATES. 



Legume without glandular hairs; flowers white. 1. R. Pseudoacacia (A, C). 



Legume glandular-hispid (in the arborescent form of No. 2) ; flowers rose color. 



Glands not viscid. 2. R. neo-Mexicana (F, H). 



Glands exuding a clammy sticky substance. 3. R. viscosa (A). 



1. Robinia Pseudoacacia L. Locust. Acacia. Yellow Locust. 



Leaves 8'-14' long, with a slender puberulous petiole, and 7-19 leaflets; turning pale 

 clear yellow late in the autumn just before falling; stipules \' long, linear, subulate, mem- 



Fig, 569 



branaceous, at first pubescent and tipped with small tufts of caducous brown hairs, be- 

 coming straight or slightly recurved spines persistent for many years and ultimately often 

 more than 1' in length; leaflets oval, rounded or slightly truncate and minutely apiculate at 

 apex, when they unfold covered with caducous silvery pubescence, at maturity very thin, 

 dull dark blue-green above, pale below, glabrous with the exception of the slight pubes- 

 cence on the under side of the slender midrib, l'-2' long and '-f ' wide; petiolules stout, 

 |'-i' in length; stipules minute, linear, membranaceous, early deciduous. Flowers open- 

 ing in May or early in June, filled with nectar, very fragrant, on slender pedicels \' long and 

 dark red or red tinged with green, in loose puberulous racemes 4'-5' long; calyx conspicu- 

 ously gibbous on the upper side, ciliate on the margins, dark green blotched with red, espe- 

 cially on the upper side, the lower lobe acuminate and much longer than the nearly trian- 



