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SYSTEMATIC BOTANY. 



GESNERACE.E. 



CoJi. Personales, JSenth. et Hook. 



Diagnosis. Soft woody shrubs or herbs, somewhat succulent, with 

 opposite or whorled wrinkled leaves, without stipules : flowers irregular ; 

 corolla perigynous or hypogynous, sympetalous ; stamens diandrous or 

 didynamous with a rudimentary 5th :" ovary half-superior, with a ring- of 

 glands or a disk, 1-celled, with two 2-lobed parietal placentas; fruit 

 capsular or succulent ; seeds numerous, with or without perisperni ; cotyle- 

 dons much shorter than the radicle. 



ILLUSTRATIVE GENERA. 



Suborder 1. GESNEREJE. Seeds 

 witli a little perisperm ; calyx partly 

 "adherent " to the capsular fruit. 



Gesnera, Mart. 



Achimenes, P. Br. 



Gloxinia, Herit. 



Suborder 2. CYRTANDREJE. Seeds 

 without perisperm fruit free, capsu- 

 lar, twisted, or baccate. 



yEschynanthus, Jack. 



Streptocarptis, Lindl. 



Cyrtandra, Forst. 



Affinities, &c. The Gesneraceae have much the aspect of Scrophu- 

 lariaceas ; and the flowers very much resemble those of Bignoniacese, but 

 their placentas are decidedly parietal ; and although Eccremocarpus con- 

 nects them with Bignoniaceee, its winged seeds and large cotyledons still 

 mark the difference from Gesneracese. The parietal placentas resemble 

 those of Orobanchaceas, which connect the Order further with Scrophu- 

 lariaceae ; but in the Gesnerece, where the seeds are perispermic, the calyx 

 is more or less adherent to the ovary. In Streptocarpus it sometimes hap- 

 pens that one of the two cotyledons becomes persistent and enlarged, 

 forming the only leaf formed b*y the plant. They are tropical plants, the 

 Gesnerece American; the Cyrtandrece more diffused, but chiefly Eastern. 

 They are of no great importance as regards their properties; some Gesnerece 

 have edible fruits : the most interesting point about them is the beauty of 

 the flowers. Most of the genera above cited are found in collections of 

 stove-plants j in their native habitations they are often epiphytic. 



COLUMELLIACEvE consist of a few species of Mexican or Peruvian 

 plants, which have been supposed to approach Jasminacese, or still more 

 closely to Gesneraceae and Rubiaceae ; but their structure is not well made 

 out. In many respects they are nearly allied to Escalloniece in Saxifra- 

 gacese. They have an adherent calyx, epigynous corolla, two stamens 

 with sinuous anthers, and an inferior 2-celled oVary with numerous ovules. 

 Seeds perispermic j embryo minute. 



OROBANCHACE^E (BROOM-RAPES) are fleshy herbs destitute of 

 green foliage (root-parasites) j corolla sympetalous ; stamens irregular, 

 hypogynous, didynamous ; the ovary 1-celled, with 2-4 parietal placentas : 

 capsule with very numerous seeds, which are minute, perispermic, with a 

 very small rudimentary embryo. Illustrative Genera : Orolanche, L. ; 

 Laihrea, L. 



