ONCIDIUM. 63 



keeled behind, 7 — 12 inches long, 2| — 3 inches broad, sub-acute, com- 

 plicate at base, slightly glaucous. Scapes robust, issuing from a carinate 

 inflated sheath, very glaucous, 3 — 4 feet long, branched along the distal 

 half, the branches short, few flowered. Flowers 1^ inches in diameter ; 

 sepals elliptic-oblong, keeled behind, the dorsal one broader than the 

 lateral two, and concave, pale broAvn with some yellow markings ; petals 

 narrower than the sepals, oblong, obtuse, undulate, incurved, chestnut- 

 brown (sometimes brown-purple) barred and margined with yellow ; lip 

 three-lobed, the intermediate lobe reduced to a small white protuberance, 

 with a purple spot ; the side lobes rotund, convex, white with some 

 purple spots at tlieir base ; crest somewhat kidney-shaped, tuberculose, 

 white with yellow and brown spots in front, reddish brown behind. 

 Column wings triangular, white ; anther beaked. 



Oncidium microchihim, Batem. in Bot. Reg. 1840, misc, 193. Liudl. in Bot. 

 Reg. 1843, t. 23. Id. Fol. Orch. Oiicid. No. 21. Saunder's Kef. Bot. II. t. 122. 



Discovered in Guatemala in 1838, and sent to Mr. Bateman by 



Mr. G. lire Skinner, who afterwards communicated to Dr. Lindley 



the following particulars respecting its habitat : — 



" I first found Oncidium microcliilum on the top of the Cuesta of 

 Puentezuelas, in 1838. It was growiug on a bare rock with a quantity 

 of dead leaves and grass about its bulbs, and its roots woven into the 

 interstices of the rock ; it Avas very much exposed to the sun, except 

 during the middle of the day, when a ledge of rock seemed to afford 

 it a little shade. I afterwards found it in great abimdance on the 

 rocky banks of the river Michatayal. I never saw it except in such 

 situations, generally exposed and always among rocks. The temperature 

 generally of the above habitats is about 20° C. (68° — 70° F.), and 

 from being exposed, cold at nights." 



It was subsequently found by Hartweg in the same country. 

 Although Mr. Bateman received the first living plants sent to 

 England, it flowered for the first time in the collection of Mr. Harter, 

 of Broughton, near Manchester, in 1841. Oncidium microchilum is 

 the only species of the section Mickochila (Cyrtochilum) known to 

 us whose habitat is north of the isthmus of Panama ; it is remarkable 

 for the almost obsolete intermediate lobe of the labellum, and for 

 the variety of colours present in the flowers, which are, however, 

 variable in this respect. 



On. Micropogon. 



Pseudo-bulbs broadly ovoid, 2 — 2| inches long, compressed with 

 acute edges, and with 2 — 3 ribs on each of the flattened sides, mono- 

 diphyllous. Leaves linear-oblong, rounded at the apex, 4 — 6 inches long. 



