522 MR. RIDLEY ON THE ORCHIDS OF MADAGASCAR. 



Disperis, Sivartz. 



All the species of this genus found in the African islands 

 belong to the section Dryopeia, characterized by its few ovate or 

 cordate amplexicaul leaves. The plants of this section are dis- 

 tributed over Eastern Tropical Africa, from Abyssinia to Natal, 

 and occur also in Southern India. 



Only two species have as yet been recorded from Madagascar, 

 D. oppositifolia, Lindl., with small flowers and a pair of opposite 

 leaves, and D. Hildebrandtii, Eeichb. f, with a single leaf and 

 larger flowers. 



D. oppositifolta, Smith in Reess Encycl. ; Lindley, Gen. § 

 Sp. Orel. PI. p. 371 ; S. Moore in Flor. Maur. et Seych. p. 331 — 

 Dryopeia oppositifolia, Thouars, Orch. lies Afr. t. 1 ; A. Rich. 

 Orch. Maur. p. 35. 



Madagascar, Thouars, I. c. ; on the ground, Atikafana, no per- 

 fume, Deans Cowan (icon.). Mauritius, Capt. CarmichaeV. Com- 

 merson ! Ins. Mascarene, no locality, Thouars ! Macgregor ! in 

 Serb. Brit. Mus. 



This is a smaller-flowered plant than D. Hildebrandtii ; it attains 

 the height of 6 or 8 inches. The pair of stem-leaves are nearly 

 opposite, ovate-lanceolate, or nearly ovate, 1 inch to 1| long, 

 \ in diameter. The capsule is narrow and elliptical, with rather 

 a long beak ; it is f inch long. 



D. Hildebrandtii, Reichenbach, Otia Hamburg, ii. p. 73. 

 Nossibe, Lokobe, Hildebrandt no. 3158 ! in Herb. Brit. Mus. 

 The whole plant is 4-5 inches tall, with the leaf f inch in 

 length. 



DESCRIPTION OF PLATE XV. 



A. Bicornelta gracilis, Lindley. 

 Fig. 1. A whole plant, nat. size. 



2. Flower enlarged. 



3. Flower enlarged, petals and sepals removed. 



4. A polliniuin, enlarged. 



B. Bicomella parviflora, Eidley. 

 Fig. 5. A whole plant, nat. size. 



6. Flower enlarged. 



7. Flower enlarged, petals and sepals removed. 



8. Column and lip from in front, enlarged. 



9. A pollinium, enlarged. 



