COHESION AND SUPPRESSION. 



253 



of a 1-merous corolla in an orchid mentioned under 

 the previous Leading, due to fusion of two lateral 

 petals. A sketch was received from Mr. G. S. Saunders 

 of a flower of Ct/pripedium Selligerum whose perianth 

 consisted of a single anterior sepal and a single 

 posterior petal, this having the form and consistence 

 of a normal lateral petal (fig. 152). 



Fig. 152. — Cyprijjedium Selligerum. Flower with monomerous 

 corolla. (O. S. Saunders.) s, sepal ; p, petal. 



Cases of suppression of the petals will next be 

 noticed. A flower of the orchid Calanthe vestita was 

 seen in which all three petals were absent. In a 

 flower of Selenipedi'iim the labellum was the sole 

 representative of the corolla. In a Kalmia all flowers 

 were entirely devoid of corolla, while the remaining 

 whorls were present in their normal condition. On 

 the other hand, the complete absence of the corolla in 



