Odontadenia 



( 123 ) 



Odontoglossum 



ODONTADENIA. 



Stove shrubs (ord. Apocynacese), of climbing 

 habit. Propagation, by seeds and cuttings, both in 

 high temperature. Soil, fibrous loam and sand. 



Principal Species : 



speciosa, 10', aut., yel., or. (tyn. Dipladenia Har- 

 risii of liotanieal Magazine 4*25). 



ODONTOOLOSSUM cuisrt-M AUKEUM (see p. 125). 



ODONTOGLOSSUM. 



Description. Unquestionably the most popular 

 genus of Orchids (ord. OrchidaceEe) is Odonto- 

 glossum, because, with very few exceptions, its 

 various members can be successfully grown in a 

 cool house, while many are very cheap, thus 

 enabling amateurs and artisans to participate in 

 the pleasures of Orchid culture and possession. 

 Though not so large-flowered as Cattleyas, or so 

 gorgeous, the Odontoglossums are bright, and have 

 a stately grace and beauty which the former do 

 not possess. The majority produce long, arching 

 spikes on which the flowers are arranged in two 

 rows ; in some the spikes are branched, notably in 

 nobile (Pescatorei), whereas in citrosmum they are 

 pendulous. In Edwardi the spikes often reach a 

 height of 4', whereas in Kossii they scarcely exceed 

 :is many inches. The pseudo-bulbs maybe quite 

 short, or 8" high, but in all cases they are com- 

 pressed, so as to show two more or less acute 

 edges ; they are generally placed close together 

 on a stout rhizome, though in the coronarium group 

 they are wide apart. It is from the base of the 

 bulb, just above the junction of the bracts, that 

 spikes appear. The prevailing colours in Odonto- 

 glossums are white, yellow, and reddish brown, but 

 purple, rose, and crimson are by no means wanting. 

 The genus includes widely different forms, and, 

 botanically, it seems to merge into Oncidium on 

 the one hand and Miltonia on the other. Within 

 the genus the species show a remarkable amount 

 of variation, as is evidenced by the fact that the 



Octomeria (of II. Don, see Eria). 

 Oci/mum (sec Ocimunt). 

 Odontocarpa (see Valeriimella). 



Royal Horticultural Society has granted awards 

 and certificates to considerably over a hundred 

 forms of the most popular of all Orchids crispum. 

 Grande is the largest flowered species, the blooms 

 measuring about 6" across, whereas in crispum the 

 flowers rarely exceed 4" and are generally 2J" to 3" 

 across. 



Distribution. Odontoglossums are entirely 

 American, and are found at varying altitudes 

 from 5,000' to 11,000' on the mountains that 

 extend along the western side, from Southern 

 Mexico to almost the southern limit of Peru. The 

 bulk of the popular species are found north of the 

 Equator, above where the Andean chain breaks up 

 into two ranges, and about where the eastern range 

 again divides, part extending eastward to the coast 

 of Venezuela. Crispum, however, does not extend 

 so far north as some do, and is practically confined 

 to a district extending 100 miles north and 100 

 miles south of the city of Bogota, associating with 

 gloriosum, luteo-purpureum, lindleyanum, etc., 

 towards its northern limit. Hallii and cirrhosum 

 live nearer the Equator, while grande and its allies, 

 though found as far north as Guatemala, are less 

 Alpine than the Columbian species, and experience 

 a wet and a dry season that must in some measure 

 be imitated in our houses if they are to be success- 

 fully managed. 



Hybrids and Seedlings. When Odontoglossums 

 were first imported in quantity it became apparent 

 that there were wide variations from the recognised 

 types, and efforts were made to refer these to 

 certain species. Soon, however, it became evident 

 that some forms could with equal reason be referred 

 to two species, and a little further investigation 

 showed that these were natural hybrids; but even 

 now it is not perfectly known how much or how 

 little influence one species has had upon another, 

 as it is quite reasonable to presume that secondary 

 and tertiary hybrids are numerous, and that even 

 what are now regarded as extreme forms of a 



OuONTOriLUSsrM AniUAX.U EltNEST AsHWOKTH 



(see p. 126). 



species may have descended from a first hybrid, 

 each succeeding generation being crossed with but 

 one of the parent species, until the influence of the 

 other original parent has been eliminated so far 

 as leading specific characters are concerned. Now 

 that success has been achieved in raising hybrid 



