﻿AN ABNORMAL ODONTOGLOSSUM CERVANTESII. 



BY HENRI HUS. 



The flowers of Odontoglossum seem frequently to be subject 

 to malformation. Penzig, in his Pflanzen-Teratologie, quotes 

 numerous cases for different species. Had it not been for 

 the fact that the case here brought forward presents some 

 aspects not ordinarily met with in the teratology of Odonto- 

 glossum flowers, a brief notice elsewhere would have been 

 considered sufficient. 



Among the plants of Odontoglossum Cervantesii cultivated 

 in the orchid house of the Missouri Botanical Garden during 

 1906, was one which bore, upon one of the scapes, five flowers 

 one of which was abnormal, the one here used for purposes of 

 illustration. The abnormafity showed itself in the first place 

 in the wings of the column which had become enlarged and 

 were provided with coloring matter. The column bore three 

 hoods with anther cases. Apparently but five floral seg- 

 ments were present. Two (pi. 9, 1, 2) of these were oval-ob- 

 long and, on account of their contour, were at once classed as 

 sepals. Two others (pi. 9, 3, 4) were broader and possessed 

 a more or less undulate margin. There was no difficulty in 

 recognizing them as petals. The fifth segment (pi. 9, 5) was 

 in form intermediate between petals and sepals and, at the 

 time, was classed as a petal, chiefly because of its position. 

 It had to be assumed that the labellum was under-developed. 



However, during 1907, the same plant again produced ab- 

 normal flowers, and observations made on these caused a 

 change in the views jusib expressed. The plant bore four 

 scapes, the flowers oi three of these being normal. The 

 fourth scape produced five flowers, of which only the terminal 

 one was normal, the four others being more or less malformed. 



The flower lowest on the scape had three sepals and but 

 one petal, the labellum, which appeared normal. On the 

 other hand, the upper sepal was twice as broad as normal. 

 The column was abnormal, the wings being absent. There 

 were two anther cases instead of one, each enclosing but a 



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