CATALPA 



Catalpa} Scopoli, Introd. Hist. Nat. 170 (1777); Bentham et Hooker, Gen. PI. ii. 1041 (1876); 

 Bureau, in Nouv. Arch. Mus. Hist. Nat. vi. 169 (1894); Dode, in Bull. Soc. Dendr. France, 

 i. 194 (1907). 



Deciduous trees, belonging to the order Bignoniaceae. Branchlets stout, with 

 thick pith ; leaf-scars elevated, orbicular, marked with a circle of dots, which are the 

 tiny scars left by the fibro-vascular bundles of the fallen petiole. Buds minute, 

 globose, immersed in the bark, with two to four external scales ; all axillary, no true 

 terminal bud being formed, the top of the branchlet dying in summer, and leaving an 

 elevated circular scar close to the upper axillary bud. Leaves simple, opposite or in 

 whorls of threes, entire or lobed, long-stalked, pinnately-nerved, without stipules. 



Flowers perfect, in terminal panicles or corymbs.^ Calyx gamosepalous, mem- 

 branous, splitting when the flower opens into two broad ovate entire lobes. Corolla 

 gamopetalous, inserted on a nearly obsolete disc ; tube broad, campanulate, oblique, 

 enlarged above into a spreading bilabiate limb, the posterior lip two-partite, the 

 anterior three-lobed. Stamens inserted near the base of the corolla, two, anterior, 

 filaments flattened, anthers bilocular and opening longitudinally. Staminodes 

 similarly inserted, three, posterior, filiform, minute or rudimentary. Ovary sessile, 

 two-celled ; style elongated, divided at the apex into two stigmatic lobes * ; ovules 

 numerous in several series on a central placenta. Fruit, a long nearly cylindrical 

 capsule, tapering from the middle to each end, persistent on the branches during 

 winter, and ultimately splitting into two valves. Seeds numerous, small, oblong, 

 compressed, inserted in two or four ranks near the margin of the woody septum, with 

 broad lateral wings, notched at the base of the seed, and ending in tufts of long 

 coarse hairs. 



The leaves of Catalpa show on their lower surface in the axils of the nerves 

 clusters of circular glands which secrete nectar, and are visited by numerous insects, 

 especially ants and bees, the latter getting honey from them as well as from the 



1 Catalpa is a corjruption of Catawba, the name of an Indian tribe that formerly occupied Georgia and the Carolinas. 



2 Bureau divides the temperate species into two sections : — 



(a) Thyrsoidea, comprising C. bignonieides, C. speciosa, and C. Kaempferi ; inflorescence a narrow panicle, the secondary 

 axes being branched. 



(*) Corymbosce, including C. Bungei and C. Fargesi ; inflorescence a corymb, with simple secondary axes. 



' The stigmatic lobes exhibit sensitive movements, opening and shutting like the leaves of a book, with the visits of bees 

 and other insects. Cf. Masters in Card. Chron. xiii. 651 (1880), and Kemer, Nat. Hist. Plants, Eng. Trans, ii. 281 (1898). 

 This phenomenon in C. bignonioides has been studied by Meehan, in Proc. Amer. Assoc. Adv. Sc. 1873, PP- 72, 73. and in 

 Bof. Gaz. viii. 191 (1883) ; and in the case of C. speciosa by Antisdale, in Bot. Gaz. \m. 171 (1883). 



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