SOBRALIA 



SOIL 



3177 



margin crenate. Guatemala. B.M. 7332. R.H. 1890: 

 12. G.C. III. 5:9. Gn. 22: 508. C.O. 2. A species 

 with fls. about as large as S. macrantha, but plants of 

 more compact habit. Var. superba, Hort. Fls. deeply 

 shaded with deep cream-yellow; throat marked with 

 orange-brown. 



BB. Lip fimbriate on margin; fls. less than 3 in. across. 



4. fragrans, Lindl. A small species with sts. about 

 1 ft. high: Ivs. 1 or 2, oblong-lanceolate, 4-5 in. long: 

 fls. 2-3 on a long peduncle, about 2 in. long, pale sulfur- 

 yellow; sepals oblong, spreading; petals similar but 

 erect; middle lobe of the labellum fimbriate on the 

 margin and having many fimbriated crests. Colombia. 

 B.M. 4882. One of the smallest of the genus. 



AAA. Fls. chiefly purple or rose. 



5. macrantha, Lindl. Fig. 3624. Sts. tufted, reed- 

 like, 4-7 ft. high, leafy all the way up: Ivs. broadly lan- 

 ceolate to oblong-lanceolate, long-pointed, 8-10 in. long: 

 fls. several at the ends of the sts., rose-purple, with the 

 front of the labellum deep purple; sepals linear-oblong, 

 4J^ in. long, reflexed and twisted; petals broader, 

 oblong, wavy above; labellum 5 in. long, with the 

 expanded portion almost circular, 3 in. across and 2- 

 lobed at the apex, very wavy; tube long, whitish within, 

 with a yellow stain in the throat and several thin yellow 

 ridges. May-July. Mex. and Guatemala. B.M. 4446. 

 F.S. 7:669." P.M. 14:241 (var). G.M. 31:559. C.O. 

 1. O. 3:75. Var. Kienastiana, Hort., (var. alba} has 

 white fls. G.C. III. 48:182. Var. filbida, Hort. Fls. 

 very large, creamy white. Var. nana, Hort. Fls. smaller 

 than type; lip dark violet-purple. 



6. Brandtiae, Kranzl. Sts. 3 ft. high: Ivs. lanceolate, 

 acuminate, 8 in. long: fls. purple-rose, paler outside, 

 with the labellum darker and having a yellow disk; 

 sepals linear; petals twice as wide; middle lobe of the 

 labellum very broad, divided into 2 diverging, rather 

 acute lobes; anther-bed with a long recurved horn on 

 each side. Resembles a medium-sized S. macrantha, 

 distinguished by the long horns of the column, and 

 black spots (not hairs) on the If.-sheaths. S. Amer. 



7. Fenzliana, Reichb. f. Sts. slender: sheaths black- 

 ish, asperulate: Ivs. oblong, acutish: fls. rose-colored; 

 sepals oblong, acute; petals obovate-cuneate, three- 

 fourths as long as the sepals; labellum spreading, front 

 portion ovate, notched, crenulate; horns of the column 

 equaling the anther. Nicaragua. Var. Slba, Hort., has 

 pure white fls. 



8. Holfordii, Sander. Plants of dwarf habit: fls. rose- 

 carmine, deeper in the lip, shading to whitish in the 

 throat. Habitat not stated by Sander. 



9. Cattleya, Reichb. f. St. stout: Ivs. oblong, acumi- 

 nate, plaited, bearing several lateral clusters of strong, 

 thick fls. of a firm fleshy texture, with purplish brown 

 sepals and petals and a purplish lip, with a white 

 column and 3 yellow lines over the center of the lip. 

 Colombia. 



10. L6wii, Rolfe. An imperfectly known species 

 intro. about 1892 from Colombia. It grows about 1J^ 

 ft. high and has fls. of a bright uniform purple. 



S. Amia?=S. Wilsonii XS. xantholeuca. G.C. III. 40:suppl. 

 Aug. 25. S. Amtsiarui=S. Wilsonii X S. xantholeuca. G. 31 : 581. 

 S. bldnda, Kranzl. Fls. 6 in. across, white, except throat and mid- 

 dle portion of disk of lip, which are golden yellow. Hab. (?). S. 

 Chdrlesworthii, Hort. Fls. rich rose-purple, with broad purple band 

 around lip and bright yellow crest. Colombia. S. Cliftonix, a 

 dwarf, wnite-fld. species, said to come from Ecuador. G.M. 53: 

 325. J.H. III. 53:75; 63:3 (both as S. Holfordii). S. Cdlma nii 

 =S. xantholeuea X S. Veitchii. S. Elizabethae=S. Liliastrum. 

 S. Ldnihoinei=S. Ruckeri. S. Lilidstrum, Lindl. Fls. large, white, 

 yellow-veined. Guiana, Brazil. S. Lucasidna, Hort. Fls. large; 

 sepals and petals white; lip soft rose-purple, throat yellow. Trop. 

 Amer. S. luminAsa=S. Holfordii X S. Wilsonii. S. Malmquis- 

 tidna, Schlecht. Fls. pale rose, with orange-yellow blotch on lip. 

 Colombia. O. 1911:59, desc. S. murdbilis=S. Veitchii X S. mac- 

 rantha Kienastiana. S. Ruckeri, Lind. & Reichb. f. Sepals and 

 petals pale rose-purple; lip with a white base, marked with a yel- 

 low band, the front of lip dark rose-purple. Colombia. G.C. III. 



30: 67. J.H. III. 48 : 531. S. schoenbrunnensis=B. xantholeuca var. 

 superba X S. macrantha. S. sessilis, Lind}. Sheaths and under 

 surface of Ivs. black-pubescent: Ivs. sessile, oblong-lanceolate: 

 fls. sessile, rose, the lip darker. Guiana. B.R.27:17. J.F. 1:104. 



S. Siebertidna=S. macrantha Kienastiana X S. Hodgkinsonii.-.S. 

 vdlida, Rolfe. Fls. about 2 in. long, fragrant, whitish yellow, with 

 deeper yellow band on lip, becoming deep orange in front. Panama. 



S. Veitchii, Hort.=S. macrantha X S. xantholeuca. Sepals oblong, 

 somewhat undulate, white, lightly tinted rose-lilac; petals oval- 

 oblong, undulate, white, tinted rose; lip ample, the limb strongly 

 tinted with lilac-violet, the throat orange, the margin strongly 

 undulate-crisped. J.H. III. 63:171. C.O. Hyb. 1. S. Wiganise= 

 S. macrantha X S. xantholeuca. G.M. 45:441. S. Wilsonii, Rolfe. 

 Fls. large, white, shaded with rose and spotted with purple. 



GEORGE V. 



SOCRATEA (named after the philosopher Socrates). 

 Palmctceas. Treated by Drude, in Engler & Prantl's 

 "Pflanzenfamilien," vol. 2, part 3, page 60, as a subgenus 

 of Iriartea, the subgenus characterized by the numerous 

 stamens, the branches of the raphe which rise from the 

 base and are united, running up to the micropyle which 

 is at the apex of the seed. 



Forgetiana, Hort. (Ceratolobus Forgetiana, Hort.). 

 Lvs. rich green, at first entire and broadly rounded, 

 later pinnate with the terminal 1ft. much larger than 

 the others. Peru. G.C. III. 51:suppl. May 25, p. xv.; 

 53:286. G.M. 55:636. Gt. 61, p. 391. 



SOIL. The soil is a superficial covering of the earth's 

 crust, more or less well adapted to the growth of plants. 

 It is usually only a few inches thick. Below this is a 

 subsoil often differing, especially in humid climates, 

 from the soil proper in color, texture, or chemical com- 

 position. A very striking definition has been suggested 

 by Sir John B. Lawes, who considered the soU to be 

 rotten subsoil, and the subsoil rotting rock. The term 

 soil is occasionally used in a more comprehensive way 

 to include both the soil and the subsoil. 



The soil adapted to the growth of the higher plants 

 consists of fragments of rocks or minerals, organic 

 matter, soil solution, and a soil atmosphere. The 

 mineral fragments vary in size from the finest clay 

 particles to gravel and even boulders. The organic 

 matter is derived from low organisms, from previous 

 vegetation, or from growing plants; as also from stable 

 manure, and occasionally fish or animal matter added 

 to the soil by man. The soil solution consists of water 

 carrying dissolved substances derived from the soil 

 grains and from the organic matter, as well as from 

 fertilizing materials artificially applied, and constitutes 

 a nutrient solution from which the plant derives its 

 mineral constituents. The soil atmosphere differs from 

 the ordinary atmosphere above the soil in being richer 

 in carbon dioxid and nitrogen, and containing more 

 water vapor and less oxygen. 



In origin there are two main classes of soils: sedimen- 

 tary soils, formed by the disintegration and decomposi- 

 tion of rocks in place; and transported soils, including 

 those of alluvial, glacial, and a?olian origin. The word 

 alluvial is here used to include all water-transported 

 material; the term is, however, frequently used in a 

 more specific sense to indicate the recent flood deposit 

 of rivers. 



Soils are classified according to their origin and their 

 mechanical and chemical composition and properties. 

 Genetically, they are classified according to the rock 

 from which they are derived, as granite soil, limestone; 

 or according to the manner of their origin, as alluvial, 

 lacustrian, or drift. Mechanically, they are classified 

 broadly into stony, gravelly, sandy, sandy loam, loam, 

 clay loam, clay, adobe, black-waxy, or according to 

 some other physical property; chemically, into calcare- 

 ous, humus, alkali, and according to other striking 

 chemical features. In the soil survey of the United 

 States Department of Agriculture a local name is 

 adopted for each type under which the specific charac- 

 ters are given; examples of this are Hartford sandy 

 loam, Norfolk sand, San Joaquin adobe. 



The physical properties of soils concern the size and 



