ACERAS. — OPHRYS. 319 



high. L. oblong, obtuse ; upper lanceolate, acute. Spike elon- 

 gated, cylindrical, dense. Bracts 3-veined. Fl. small, yellowish- 

 white, fragrant. — Mountain pastures. P. VI. VII. 



3. AcERAS R. Br. 



1. A. anthropophora (R. Br.) ; lip 3-parted, segments linear- 

 filiform, middle one bifld and often with an intermediate tooth. 

 —E. B. 29. R. xiii. 357.— Root-knobs ovate. Height 8—12 in. 

 Spike long, lax. Fl. greenish-yellow. Sep. ovate, acute, con- 

 nivent, margined with purple, including the linear-lanceolate ob- 

 tuse petals. — Dry chalky places. P. VI. E. 



4. Habenaria R. Br. Frog Orchis. 

 * Spur very short, usually inflated. Cceloglossum Hartm. 



1. H. viridis (R. Br.) ; spur 2-lobed, lip linear flat 3-pointed 

 middle point the shortest. — Orchis Sm., E. B. 94. R. xiii. 434. 

 Peristylus Lindl. — Lip with 3 tubercles at its base, 1 central, 2 

 lateral. Stigma oblong, slightly emarginate above. Glands of 

 the pollen-masses connected by an elevated transverse line. Sep. 

 and pet. connivent. Root-knobs palmate. Fl. green, lip browner. 

 St. 6—8 in. high.— Pastures. P. VI. VII. Frog Orchis. 



** Spur slender. Platanthera Rich. Butterfly Orchis. 



2. H. bifolia (R. Br.) ; spur twice as long as the germen, lip 

 linear entire, pet. connivent obtuse, anth. oblong truncate its cells 

 parallel— E. B. S. 2806. R. xiii. 429.— About a foot high. Root- 

 1. usually 2, elliptical. Stem-1. small, lanceolate, resembling the 

 bracts. Spike slender. Fl. white. Central line between the 

 cells of the anther a furrow in front and a keel behind. Stigma 

 truncate, emarginate with pointed lobes. — Heathy places. P. 

 VI. VII. 



3. H. chlorantha (Bab.); spur twice as long as the germen, 

 lip Unear entire, pet. connivent obtuse, anth. truncate its cells 

 twice as distant at the base as at the top. — Orchis bifolia Sm., 

 E. B. 22. R. xiii. 430. — Usually taller and stouter than the pre- 

 ceding. Spike usually lax, but sometimes dense. Fl. lai'ger. 

 Central Une between the cells of the anther a prominent ridge 

 in front and a groove behind. Space between the bases of the 

 anth. -cells usually, not always, spread open. Stigma very broad, 

 slightly pointed in the middle. — Moist woods and thickets. P. 

 V. VI. 



5. Ophrys Linn. 



1. 0. apifera (Huds.); Hp tumid 5-lobed, 2 lower lobes pro- 

 minent and with a hairy base, 2 intermediate reflexed truncate, 



