324 MB. G. BENTHAM ON OBC1I1DEJE. 



were sessile en the gland or scale in the one, and separately 

 stipitate in the other. The fact appears to be, however, that the 

 stipites exist in both species, but are reduced to a slightly pro- 

 minent ring or are very short (as figured, Bot. Mag. t. 3573) in 

 Scuticaria Steelii, Lindl., whilst they are more conspicuous in 

 JBifrenaria Hadwenii. 



Maxillaria, the principal genus of the subtribe, w r as at one 

 time a kind of receptacle for a great variety of American Vandea?, 

 and has since been variously extended or cut up. Reduced to 

 Reichenbach's section Colacaxtrum, it is a not unnatural genus of 

 above a hundred species, distributed into two generally distinct 

 series, but which occasionally run into each other : — 1. Acaules, 

 in which the only leaves are the one or two which terminate the 

 pseudobulbs, the 1-flowered scapes proceeding from the short 

 rhizome. This series corresponds to the genus JPsittacoglossum 

 of Llave and Lexarsa, who applied the name of Maxillaria to 

 Lindley's Xylobhim. It includes also Dicrypta or Heterotaxis of 

 Lindley. 2. Caulesccntes, in which the rhizome is more or less 

 extended beyond the pseudobulbs into a stem clothed with di- 

 stichous leaf-sheaths, the upper ones often bearing leafy lamina?, 

 the peduncles axillary in the lower leaf-sheaths ; the habit thus 

 approaching that of Camaridium. 



Camaridinm, Lindl., and Dicha?a, Liudl., of about twelve species 

 each, and OrnitMdium, Salisb., about twenty species, are genera 

 evidently very nearly allied to each other, but very difficult to 

 characterize efficiently. In many species the floral structure is 

 as yet imperfectly known. All have the rhizome more or less 

 produced into erect ascending or branching steins, with distichous, 

 often equitant leaf-sheaths, mostly bearing leafy laminae, and the 

 1-flowered peduncles or pedicels axillary. In Camaridinm, which 

 in many respects approaches the caulescent Maxillarias, pseudo- 

 bulbs, bearing a single large petiolate coriaceous leaf, are often 

 produced. These pseudobulbs never appear in Dichcca. In both 

 these genera the peduncles are solitary. Ornithidium has occa- 

 sionally pseudobulbs, and, though showing great affinity to Cama- 

 ridinm and DicJ/cea, differs from Maxillarieso generally in the 

 peduncles or pedicels clustered in the axils, in the less prominent 

 or obscure mcntuin, and the pollen-masses have sometimes 

 appeared to me to be free from the stipes. The structure of the 

 flowers, however, of most species requires a much more perfect 

 investigation than can be made with our specimens. The genus 



