836 



ISATIS 



ISOLOMA 



IS ATIS (meaning obscure). Crucifene. This includes 

 the Dyer's Woad, I. tinctoria, formerly cult, for a blue 

 dye, but no longer advertised. Caesar relates that the 



1184. Isoloma Tydaea (X K). 



ancient Britons used the Woad for staining their bodies, 

 and the word Britain itself comes from an old Celtic 

 word meaning painted. Before indigo became common 

 in Europe, the Dyer's Woad produced the chief blue 

 coloring matter for woolen cloth. The introduction of 

 indigo in the seventeenth century destroyed this im- 

 portant industry, not without opposition. Dioscorides 

 and Pliny mention both the Dyer's Woad and indigo. 



/. tinctdria, Linn., is rather tall, glabrous and glau- 

 cous: stem-lvs. lanceolate, entire, sessile, somewhat ar- 

 row-shaped: fls. small, yellow, borne in early summer, 

 on panicled racemes. Instead of apod, opening length- 

 wise by valves, it has a closed fruit like on the samara 

 of an ash, 1-celled, 1-seeded. indehiscent, wing-like. It 

 is a biennial, and common in Europe. 



ISCHARUM. See Biarum. 



ISMENE. Now referred to Hymenocallis . 



ISNARDIA. Includes a few species of Ludwigia. 



ISOCHlLUS (Greek, equal lip). Orchiddcece. A genus 

 of no commercial value. Plants epiphytic, with tall, 

 slender, leafy stems, without pseudobulbs, bearing a few 

 small fls. at the summit. Sepals erect, free, keeled ; pet- 

 als similar but plane ; labellum like the petals and united 



with them to the base of the column, somewhat sigmoid 

 below the middle: column erect, long, without wings: 

 polliuia 4. About 5 species in Braz., Mex., and W. Ind. 



linearis, R. Br. Slender, 1-1% ft. high, leafy: Ivs. dis- 

 tichous, linear, striate, obtuse, emarginate, 1^ in. long: 

 fls. purple, borne in a short, terminal spike. March. 

 Growing on rocks and trees in thick woods, Jamaica, 

 Trinidad, Brazil, etc. B.R. 9:745. L. B.C. 14:1341. 



H. HASSELBRING. 

 IS0LEPIS. See Scirpus. 



ISOLOMA (equal border). Gesner- 

 aceve. Includes Tydcea. Sixty or more 

 tropical American plants, very closely 

 allied to Gesneria and Achimenes. 

 From Gesneria distinguished by ab- 

 sence of well-formed tubers and char- 

 acters of capsule and anthers, and the 

 5 lobes of the disk equal; from Achim- 

 enes in the more tubular flowers ant 

 lobed disk. The culture is the 

 as for Achimenes and Gesneria. S( 

 of the newer hybrids germinatequicklj 

 and plants bloom the same year. It 

 probable that the pure species are 

 in the trade. Like Achimenes, G( 

 neria and Gloxinia, they have 

 much hybridized and varied. It 

 probable" that they are hybridized wit 

 Achimenes and Gesneria. Tydsea is 

 garden genus. It is not known h( 

 the current forms have original 

 Some of the recent ones have frinj 

 fls. (Gn. 55:1223). 



Tydaea ( Achimenes picta, Benth. 

 data picta, Dene.). Fig. 1184. One to 

 ft., hairy: Ivs. cordate-ovate, coars 

 serrate, spotted and reticulated wit 

 pale green or silvery green, with 

 broad light zone down the center: fls 

 single, on long, axillary stems, nc 

 ding, the orifice oblique and lobes 

 tuse, the upper longitudinal half of 

 fl. red, the lower half yellow and 

 spotted. Colombia. B.M. 4126 (adapt 

 in Fig. 1184). B.R. 31:42. F.S. 1:17- 

 18. On this species Decaisne founded 

 the genus Tyda in 1848. This species 

 has been called Isoloma pictnm, but 

 this name was taken by Planchon in 

 1850 to '51 for the Gesneria picta 

 Hook., which is a very -different plai 

 See F.S. 6:586. B.M. 4431. This latt 

 plant, the first Isoloma pictum, is 

 parently not in commerce, 

 aniabile, Mottet (Tydcea amdbilis, Planch. & Lind. 

 Erect, hairy: Ivs. ovate, more or less tapering to 



1185. Isoloma Jaliscanum (XK). 



petiole, bluntly serrate, purplish on the veins: 

 hairy, pendent, dark rose dotted with purple, paler insi 

 Colombia. B.M. 4999. R.H. 1859, p. 25. F.S, 10:1070. 



