382 ORCHIDS 



Odontoglossum. 



Staiiroiih's Sj'ii. i-h-gaiitiii.s \-ar. 



sli'lli?)iiii'iiis Sj'ii. e.xicllens var. 



tt'iitaiiilaluni Syn. ciispidatian. 



Tt'xativuni su]:)])Osed fitaciilatiDii and apten/iji. 



Victor Syn. degaiis. 



M'amerianuni sup]50sed apterioii and Rossii . 



U'atfiaiiiiiii (Fig. 127) Uan-ynnum a\v\ LindU'yainim. 



U't-ndlandiauiini supi;)Osed crispuni LcdiDiaiini and L'irrhosinn. 



JVilckt'oiunii (Fig. 128) supposed cn'spiiiii and hiteo-pufpiiirunt. 



ONCIDIUM. 



A very large number of epiphytes, belonging to the tribe 

 Vandece^ and exclusively natives of tropical America — 

 being generally diffused from Mexico and the West Indies 

 to Bolivia and Brazil — are included in this genus. The 

 name given by Swartz is from o?tkos, a tumour, and is 

 in reference to the warty crest on the base of the labellum. 

 Over 256 species have been described, but it is questionable 

 if the whole of these are distinct. No less than i8o of 

 the number are supposed to be in cultivation in Europe 

 — a fact which goes to prove that a large proportion of 

 the plants are sufficiently ornamental for the garden. 

 There are, however, man)- which, on account of their 

 lack of size or of attractive colours, do not call for 

 description here. We have selected about thirty distinct 

 species as representative of the genus, and as compris- 

 ing all that are worthy of being classed among first-rate 

 garden Orchids. 



Botanically considered, the genus is, with few excep- 

 tions, a natural one, of well-marked characters and 

 easily distinguished from its allies, Odontoglossum and 

 Miltmiia. There are certainly links that connect these 

 with each other. With regard to Miitoitia, Reichenbach 

 himself proposed to merge that genus in Oncidium. 

 For garden purposes, however, this would have been a 

 mistake, and it has never been insisted on. The floral 

 characters that distinguish Oncidiiiin are the short and 

 thick column, with its two ear-like appendages, the lip 

 forming an angle with the column, the usually warty crest 

 on the latter, and its generally large, spreading front lobe. 

 In habit, size, and shape of pseudo-bulb, in form and size 

 of leaves, and in form of inflorescence, there is considerable 

 \'ariation amiongst Oncidiums. The blossoms also ^•ar^' 



