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CXCVIII. SPIGELIACEiE. The Wormseed Tribe. 



SpigeliacejE, Martius, N. G. et Sp. 2. 132. (1828.) 



Diagnosis. Monopetalous dicotyledons, with regular flowers, a superior 

 2 -celled ovarium, several ovules, a valvate corolla, dry fruit, and opposite 

 leaves. 



Anomalies. 



Essential Character. — Calyx inferior, regularly 5-partcd. Corolla regular, with 51obea, 

 which have a valvate aestivation. Stamens 5, inserted into the corolla all in the same line ; 

 pollen 3-cornercd, with globular angles. Ovarium superior, 2-celled ; style articulated with 

 it, inserted ; siigma simple. Fruit capsular, 2-celled, 2-valved, the valves turned inwards at 

 the margin and separating from the central placenta. Seeds several, small ; testa single ; 

 embryo very minute, lying in copious fleshy albumen, with the radicle next the hilum. — Her- 

 baceous plants or undcr-shrubs. heaves opposite, entire, with stipula:, or a tendency to pro- 

 duce them. Flowers arranged in 1-sided spikes. Pubescence simple or stellate. 



Affinities. This order was founded by Dr. Von Martius, from whose 

 splendid work upon the Brazilian Flora I extract the following remarks : 

 " There are many reasons for separating Spigelia from Gentians ; and I am 

 the more disposed to attend to those reasons, from seeing daily instances of the 

 necessity of establishing new orders, to avoid weakening the characters of old 

 ones. For example, Aquilarineae, Datisceae, Hamamelideaa, and other orders, 

 constructed upon a few species, are so many instances of this practice, by which 

 the science is both embellished and strengthened by our most skilful botanists. 

 With regard to Spigelia, if we retain it among Gentianeae, I do not know how 

 we are to distinguish that order with certainty from those in its neighbourhood ; 

 for this genus approaches Scrophularinese in the division of the two valves of 

 the fruit, and in the central, not parietal, origin of the placentae ; and Rubiaceee 

 in the insertion of the style into the ovarium, and the distention of the petiole 

 into the form of a stipula. Scrophularineae are, indeed, so nearly related to 

 Gentianeae, that the best botanists have admitted that there are scarcely any 

 marks of distinction between them, besides the regular number of the stamens 

 of the latter, and the simplicity of the valves of the capsule." (The position 

 of the pericarpial leaves with relation to the axis of inflorescence, is now known to 

 be acertain mark of distinction between Gentianeae and Scrophularineae.) "Some 

 may possibly adduce the irregularity of the corolla of Scrophularinese, and the ori- 

 gin of the placenta? from the mere inflexion of the valves of the capsule in Gen- 

 tianeae; but it must be remembered, that there are certain genera of Scrophu- 

 larineae, such as Limnophila, Xuaresia, Ourisia, and Veronica, the corolla of 

 which is regular or nearly so ; and that certain Gentianeae, for instance Exacum 

 and Schubleria,have several placentas, which, although deriving theirorigin from 

 the inflexion of the valves of the capsule, yet become loose and more or less 

 distinct. Others may refer to the aestivation as another source of differences, 

 it being in Gentianeae, on account of the lateral and somewhat contorted 

 twisting of the nearly equal segments, contorted-convolutive, and in Scrophulari- 

 neae, on account of the involution of the unequal segments towards the centre 

 of the flower, merely imbricated ; but these differences, on account of the dif- 

 ferent forms of the corolla in these extensive orders, are scarcely distinguisha- 

 ble, and are more available in the theory than in practice. Besides, in Spige- 

 lia the aestivation is different from either, being valvate, with the margins of the 

 segments often protruding into acute angles, and is more like that of Rubia- 

 ceee (Cinchonaceae). It must be admitted, that while the seeds of Gentianeae 

 are uniformly indefinite, those of Spigelia are definite, or nearly so. Upon all 

 these considerations, and to avoid confusing the distinctive characters of the 



